Charged particle beam exposure system and charged particle beam exposure method

• US 5,260,579 A
• Filed: 03/13/1992
• Issued: 11/09/1993
• Est. Priority Date: 03/13/1991
• Status: Expired due to Term

• Current Assignee: Fujitsu Semiconductor Limited (Fujitsu Limited)
• Original Assignee: Fujitsu Limited
• Inventors: Takahashi, Yasushi, Yamada, Akio, Yasuda, Hiroshi, Oae, Yoshihisa, Fueki, Shunsuke, Kai, Junichi, Kawashima, Kenichi, Sakamoto, Kiichi
• Primary Examiner(s): Dzierzynski, Paul M.
• Assistant Examiner(s): NGUYEN, KIET TUAN
• Application Number:
  US07/851,400
• Time in Patent Office: 606 Days
• Field of Search: 250/492.2, 250/492.22, 250/492.23, 250/398
• US Class Current: 250/492.2
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: H01J 2237/0435 Multi-aperture
• CPC Class Codes: H01J 37/09 Diaphragms; Shields associated with electron or ion-optical arrangements; Compensation of disturbing fields
• CPC Class Codes: H01J 37/3177 Multi-beam, e.g. fly's eye, comb probe

Abstract

A charged particle beam exposure system is directed to an exposure process of an electron beam for sequentially scanning an electron beam employing a blanking aperture array including a plurality of blanking apertures. The system facilitates re-focusing for compensation of focus error due to Coulumb effect and makes wiring the blanking aperture array easier. The system further allows exposure without an irradiation gap. The blanking aperture array 6 is formed with a plurality of said blanking apertures 62 arranged in a two-dimensional configuration. A control system 24 controls the blanking aperture array 62 to set the blanking aperture to the ON state where the charged particle beams pass through the blanking aperture and reach the object 19 to be exposed or the OFF state where the charged particle beams cannot reach the object 19 to be exposed. The other control system of the control means performs a control so that a plurality of said charged particle beams that have passed through different blanking apertures of said blanking aperture array overlaps and is irradiated a plurality of times onto the specified position or the peripheral position in the vicinity of the specified position of the object to be exposed to the charged particle beams.

Claims

1. A charged particle beam exposure system comprising:

a charged particle beam generating means for generating a charged particle beam;

a blanking aperture array means for shaping said charged particle beam generated by said charged particle beam generating means and having a plurality of blanking apertures arranged in two dimensional form;

a stage means for holding an object to be exposed;

a deflection means for deflecting the charged particle beam passing through said blanking aperture array means by a specified amount in order to irradiate the charged particle beams onto the specified position of said object to be exposed;

wherein said system further comprising;

a first means for irradiating a pattern formed by said charged particle beams arranged in two dimensional configuration on a first region specified on said object to be exposed;

a second means for successively irradiating the pattern formed by said charged particle beams arranged in two dimensional configuration on a second region having an overlapping region to the first region;

and wherein said first and second means are constructed so that when said charged particle beams are irradiated to said object to be exposed, a first charged particle beam passing through a first blanking aperture irradiates a specified first region on said object to be exposed by said first means and a second charged particle beam passing through a second blanking aperture arranged next to said first blanking aperture irradiates a region closely arranged to said specified first region by said second means, and thus said specified position in said overlapping region is irradiated a plurality of times by respective charged particle beams, each having a certain irradiation amount set by, dividing a total irradiation amount.

2. A charged particle beam exposure system according to claim 1, wherein assuming that the width of each of said blanking apertures in the row direction is S and the number of blanking aperture columns having different arrangement phases is n, the distance of each blanking aperture in adjacent blanking aperture columns, in a row direction, is set to be nS or a value approximate to nS.

3. A charged particle beam exposure system according to claim 1, wherein the total width of each blanking aperture forming said blanking aperture array, in the row direction is at least equal to the width of a sub-field to scan said charged particle beam.

4. A charged particle beam exposure system according to claim 1, wherein, in said blanking aperture array, a plurality of blanking apertures forming one column has a different arrangement phase to a plurality of blanking apertures forming an adjacent column.

5. A charged particle beam exposure system according to claim 1, wherein a plurality of columns having different arrangement phases of a plurality of blanking apertures are formed into one unit, and a plurality of units are repeated.

6. A charged particle beam exposure system according to claim 1, wherein respective charged particle beams passing through the blanking aperture group formed by a plurality of blanking aperture columns mutually having different arrangement phases, are positioned on the same row line of the irradiation exposure section formed on said object and is controlled by said control means so as to be irradiated between said irradiation exposure sections.

7. A charged particle beam exposure system according to claim 1, wherein electrode means is provided for each blanking aperture of said blanking aperture array, which can be set at ON state to pass said charged particle beams generated by said charged particle beam generating means to reach said object and at OFF state to deflect said charged particle beam upon passing through said blanking aperture so as not to reach said object;

said electrode means being selectively set at ON and OFF state depending upon the presence and absence of a predetermined voltage by said blanking aperture array control means.

8. A charged particle beam exposure system according to claim 7, wherein said electrode means comprises two mutually independent electrode sections provided in the vicinity of two opposing surfaces of said blanking aperture, and one of said electrode section forming a variable voltage electrode connected to said blanking aperture array control means and the other forming a constant voltage electrode connected to a constant voltage source.

9. A charged particle beam exposure system comprising:

a charged particle beam generating means for generating a charged particle beam;

a blanking aperture array means for shaping said charged particle beam generated by said charged particle beam generating means and having a plurality of blanking apertures arranged in two dimensional configuration;

a stage means for holding an object to be exposed;

a deflection means for deflecting the charged particle beam passing through said blanking aperture array means by a specified amount in order to irradiate the charged particle beams onto the specified position of said object to be exposed;

a control means for controlling at least one of said means; and

wherein said blanking aperture array means having a plurality of blanking apertures arranged in two dimensional configuration, and said control means including a control means for controlling said blanking aperture array means;

and wherein said blanking aperture array controlling means independently controls respective blanking aperture to continuously form a pattern to be exposed to a specific position of said object to be exposed so as to set the blanking aperture to ON state where the charged particle beams generated by said charged particle beam generating means pass through the blanking aperture and reach the object to be exposed or the OFF state where the charged particle beams cannot reach the object to be exposed and thereby a plurality of said charged particle beams irradiate a predetermined position on said object to be exposed, respectively, so that a pattern exposed on said position formed by one of said charged particle beams contacts another pattern thereof formed by another charged particle beam without being separated from each other, and further said blanking aperture array controlling means controlling said blanking apertures to move a predetermined pattern to be exposed on said object to be exposed in a predetermined direction along said blanking aperture array means, and when the pattern is moved, to irradiate a plurality of said charged particle beams passing through a plurality of blanking apertures newly selected to form a predetermined pattern at a region that overlaps with said predetermined region to which a plurality of said charged particle beams passing through a plurality of blanking apertures previously selected to form said predetermined pattern, are irradiated.

10. A charged particle beam exposure system according to claim 9, wherein said specific region of said object to be exposed is exposed to the predetermined pattern by scanning the charged particle beam utilizing said deflection means and in synchronism with deflecting scan of said deflection means, said blanking aperture array control means controls shifting of said specific pattern formed in said blanking aperture array in one direction so that said overlapping region comprising, the specific position or the position in the vicinity of said specific position in said specific region of said object can be irradiated in an overlapping manner with a given time interval with a plurality of said charged particle beams passing through different blanking apertures.

11. A charged particle beam exposure system according to claim 9, wherein a plurality of said blanking apertures in said blanking aperture array have the same opening areas and arranged in a plurality of rows and a plurality of columns to form a matrix form array.

12. A charged particle beam exposure system according to claim 9, wherein wiring is provided utilizing a space extending from both column direction ends of said blanking array to the clearance between rows of said blanking apertures toward the inside of a control signal line from said blanking aperture array control means and connects said control signal line to respective variable voltage electrodes of respective blanking aperture, and said constant voltage source wiring is arranged in the vicinity of the center of said blanking to aperture array connect said constant voltage source wiring to said constant voltage electrodes of respective blanking apertures.

13. A blanking aperture array means which includes a plurality of blanking apertures having the same opening, wherein said apertures are classified into a first blanking aperture array group in which a plurality of said blanking apertures are arranged both in row direction and column direction to form a matrix array configuration and a second blanking aperture array group in which a plurality of said blanking apertures are arranged both in row direction and column direction to form a matrix array configuration and wherein in the column direction, one row of the blanking apertures in said first blanking aperture array group and one row of the blanking apertures in said second blanking aperture array group being alternately arranged each other, while in said row direction, one blanking aperture in said first blanking aperture array group is arranged in a portion opposite to a space formed between adjacent two blanking apertures in the row direction in said second blanking aperture array group, and wherein a pitch length in said row direction formed between one blanking aperture of said first blanking aperture array group and one blanking aperture of said second blanking aperture array group, is set at a predetermined value so that when two different charged particle beams passed through two adjacently arranged blanking apertures, each of which belonging to one of said first and second blanking aperture array groups, respectively, are irradiated the object to be exposed, each of portions exposed with said each one of said different charged particle beams, respectively, is connected to each other on said object.

14. A blanking aperture array means as set forth in claim 13, wherein, in said blanking aperture array means, a plurality of blanking apertures forming one column have different arrangement phases to a plurality of blanking apertures forming an adjacent column.

15. A blanking aperture array means as set forth in claim 14, wherein, assuming that the width of each of said blanking apertures in the row direction is S and the number of blanking aperture columns having different arrangement phases in n, the distance of each blanking aperture in adjacent blanking aperture columns, in the row direction, is set to be nS or a value approximate to nS.

16. A blanking aperture array means as set forth in claim 14, wherein a plurality of columns having different arrangement phases of a plurality of blanking apertures are formed into one unit, and a plurality of units are repeated.

17. A blanking aperture array means as set forth in claim 13, wherein the total a width of each blanking aperture forming said blanking aperture array means, in the row direction, is at least equal to the width of a sub-field to scan said charged particle beams.

18. A method for exposing an object by a charged particle beam exposure system having means for generating a charged particle beam, a blanking aperture array comprising a plurality of selectively and individually controllable blanking apertures arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns, and means for repeatedly scanning the blanking aperture array with the beam and for selectively controlling and thereby enabling the individual apertures thereof thereby to permit the scanning beam to pass through the individual, selectively enabled apertures of the array, means for holding an object to be exposed and deflecting means for deflecting the beam, after passing through a selectively enabled aperture of the array, to scan the object in a corresponding position thereon, said method comprising:

defining potential target positions to be exposed on the object, the target positions arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns corresponding to the two-dimensional configuration of the apertures of the blanking aperture array;

moving the object, as held by the holding means, relative to the blanking aperture array and in a first direction parallel to the respective columns of the blanking aperture array and of the target positions;

in a first step, scanning an array to expose a desired pattern of first target positions in a first row on the object with the beam in accordance with selectively enabling the corresponding apertures of the first row of apertures of the array;

in a second step, moving the object relative to the array in the first direction and so as to position the first row of potential target positions on the object in correspondence with a second, next successive row of apertures of the array and thereby to position a second row of potential target positions on the object with the first row of apertures of the array, and selectively and individual enabling the apertures of the second row of the array in accordance with the desired pattern of the first target positions of the first row on the object and, simultaneously, selectively and individually enabling the apertures of the first row of the array in accordance with a desired pattern of second target positions in a second row on the object, and scanning the array with the beam so as to expose the desired pattern of first target positions in the first row and second target positions in the second row on the object with the beam, in accordance with the selectively enabled and corresponding apertures of the respective, second and first rows of apertures of the array; and

performing the successive steps until each row of the target positions on the object has been exposed by the scanning beam through the correspondingly enabled apertures, in succession, for each row of apertures of the array.

19. The method for exposing an object by charge particle beam exposure system as recited in claim 18, wherein the blanking apertures of the blanking aperture array have the same dimensions.

20. The method for exposing an object by a charge particle beam exposure system as recited in claim 18, wherein the deflecting means comprising a sub-field having a width which is equal to or less than the total width of each blanking aperture forming the blanking aperture array in the row direction.

21. A method for exposing a charged particle beam to an object to be exposed according to claim 18, wherein:

the deflection means comprises a lens means,

and the control means calculates the total sum of the number of the blanking apertures in the blanking aperture array to be selectively controlled to irradiate a target position and the lens means, simultaneously, compensating the focus error due to the Coulomb effect of the charged particle beams by means of a refocusing means.

22. A method for exposing a charged particle beam to an object to be exposed according to claim 18, wherein the control means calculates the total sum of a number of blanking apertures in the blanking aperture array to be selectively controlled to irrigate a target position and simultaneously, the deflection means applies a deflection signal to deflect the charged particle beam to compensate and offset the position of the beam from an intended position thereof.

23. A method for exposing an object by a charged particle beam exposure system having means for generating a charged particle beam, a blanking aperture array comprising a plurality of selectively and individually controllable blanking apertures arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns, and means for repeatedly scanning the blanking aperture array with the beam and for selectively controlling and thereby enabling the individual apertures thereof thereby to permit the scanning beam to pass through the individual, selectively enabled apertures of the array, means for holding an object to be exposed and deflecting means for deflecting the beam, after passing through a selectively enabled aperture of the array, to scan the object in a corresponding position thereon, said method comprising:

defining potential target positions to be exposed on the object, the target positions arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns corresponding to the two-dimensional configuration of the apertures of the blanking aperture array;

moving the object, as held by the holding means, relative to the blanking aperture array and in a first direction parallel to the respective columns of the blanking aperture array and of the target positions;

in a first step, scanning an array to expose a desired pattern of first target positions in a first row on the object with the beam in accordance with selectively enabling the corresponding apertures of the first row of apertures of the array;

in a second step, moving the object relative to the array in the first direction and so as to position the first row of potential target position on the object in correspondence with a second, next successive row of apertures of the array and thereby to position a second row of potential target positions on the object with the first row of apertures of the array, and selectively and individually enabling the apertures of the second row of the array in accordance with a desired pattern of peripheral positions in the vicinity of the first target positions of the first row on the object and, simultaneously, selectively and individually enabling the apertures of the first row of the array in accordance with a desired pattern of second target positions in a second row on the object, and scanning the array with the beam so as to expose the desired pattern peripheral positions in the vicinity of first target positions in the first row and second target positions in the second row on the object with the beam, in accordance with the selectively enabled and corresponding apertures of the respective, second and first rows of apertures of the array; and

performing the successive steps until each row of the target positions on the object has been exposed by the scanning beam through the correspondingly enabled apertures, in succession, for each row of apertures of the array.

24. The method for exposing an object by charge particle beam exposure system as recited in claim 23, wherein the blanking apertures of the blanking aperture array have the same dimensions.

25. The method for exposing an object by a charge particle beam exposure system as recited in claim 23, wherein the deflecting means comprising a sub-field having a width which is equal to or less than the total width of each blanking aperture forming the blanking aperture array in the row direction.

26. A method for exposing an object by a charged particle beam exposure system having means for generating a charged particle beam, a blanking aperture array comprising a plurality of selectively and individually controllable blanking apertures arranged in a two-dimensional configuration of parallel rows and N groups of transverse, parallel columns, wherein N is an integer and the blanking apertures in each column of a group have a width of S in the row direction and the distance of each blank aperture in adjacent blanking aperture rows is approximately NS, and means for repeatedly scanning the blanking aperture array with the beam and for selectively controlling and thereby enabling the individual apertures thereof thereby to permit the scanning beam to pass through the individual, selectively enabled apertures of the array, means for holding an object to be exposed and deflecting means for deflecting the beam, after passing through a selectively enabled aperture of the array, to scan the object in a corresponding position thereon, said method comprising:

defining potential target positions to be exposed on the object, the target positions arranged in a two-dimensional configuration of parallel rows and N groups of transverse, parallel columns corresponding to the two-dimensional configuration of the apertures of the blanking aperture array;

moving the object, as held by the holding means, relative to the blanking aperture array and in a first direction parallel to the respective columns of the blanking aperture array and of the target positions;

in a first step, scanning an array to expose a desired pattern of first target positions in a first row on the object with the beam in accordance with selectively enabling the corresponding apertures of the first row of apertures of the array;

in a second step, moving the object relative to the array in the first direction and so as to position the first row of potential target positions on the object in correspondence with a second next successive row of apertures of the array and thereby to position a second row of potential target positions on the object with the first row of apertures of the array, and selectively and individually enabling the apertures of the second row of the array in accordance with a desired pattern of third target positions in the first row on the object and, simultaneously, selectively and individually enabling the apertures of the first row of the array in accordance with a desired pattern of second target positions in the second row on the object, and scanning the array with the beam so as to expose the desired pattern of third target positions in the first row and second target positions in the second row on the object with the beam, in accordance with the selectively enabled and corresponding apertures of the respective, second and first rows of apertures of the array; and

performing the successive steps until each row of the target positions on the object has been exposed by the scanning beam through the correspondingly enabled apertures, in succession, for each row of apertures of the array.

27. The method for exposing an object by charge particle beam exposure system as recited in claim 26, wherein the blanking apertures of the blanking aperture array have the same dimensions.

28. The method for exposing an object by a charge particle beam exposure system as recited in claim 26, wherein the deflecting means comprising a sub-field having a width which is equal to or less than the total width of each blanking aperture forming the blanking aperture array in the row direction.

29. A method for exposing a charge particle beam to an object to be exposed according to claim 26, wherein the beam irradiation intensity of the pattern to be exposed on the surface of the object is selected as an integer from 1 to N, and the integers of the irradiation intensity are selected so that the beam irradiation intensity at the inside of the pattern is lower than that of the circumferential portion of the pattern.

30. A method for exposing a charged particle beam to an object to be exposed according to claim 26, wherein the beam irradiation intensity of the pattern to be exposed on the surface of the object is selected as an integer from 1 to N, and the region outside of the pattern to be exposed at the integer value of N, is exposed by the lower irradiation intensity to form a smaller pattern than the pattern.

31. A method for exposing an object by a charged particle beam exposure system having means for generating a charged particle beam, a blanking aperture array comprising a plurality of selectively and individually controllable blanking apertures arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns, and means for repeatedly scanning the blanking aperture array with the beam and for selectively controlling and thereby enabling the individual apertures thereof thereby to permit the scanning beam to pass through the individual, selectively enabled apertures of the array, means for holding an object to be exposed and deflecting means for deflecting the beam, after passing through a selectively enabled aperture of the array, to scan the object in a corresponding target position thereon, said method comprising:

defining the respective positions of the blanking apertures within the blanking aperture array in accordance with the two-dimensional configuration of parallel rows and transverse, parallel columns, the columns being grouped in parallel stages and each stage comprising a common number of plural columns including a first and successive columns, the respectively corresponding apertures of the successive columns of each of the plurality of stages being successively spaced and off-set in the column direction and the respective blanking apertures of the respective, first and successive columns of each of the plural stages being aligned in respective rows of a row alignment pattern, the row alignment pattern thereby including plural sets, each set comprising a number of first and successive alignment rows equal to the common number of the columns of apertures in each of the plural stages;

defining potential target positions to be exposed on the object, the target positions being arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns corresponding to the two-dimensional configuration of the array and including plural, adjacent target positions in each of plural columns and arranged in respectively corresponding target position rows, the rows being grouped in plural sets, each set of plural rows, the plural sets of target position rows respectively corresponding the plural sets of blanking aperture alignment rows and the first and successive target position alignment rows of each set respectively corresponding to the respective blanking apertures of the first and successive columns of blanking apertures of each stage thereof, of the array;

moving the object relative to the blanking aperture array in a succession of steps, each step including a set of plural substeps comprising a first and successive substeps, equal in number to the number of first and successive columns in each stage of plural columns of the blanking aperture array, and thereby in a first step and associated first substep, scanning the blanking aperture array with the beam to expose a desired pattern of first target positions in the corresponding first row alignment position of the plural sets thereof and in a first column of target positions on the object, in accordance with selectively enabling the corresponding apertures of the first alignment row of apertures of the first column thereof, of the blanking aperture array;

in a second subset of the first step, moving the object relative to the array in the first direction and so as to position the second alignment row, of each of the plural sets thereof, of potential target positions of the first column thereof on the object with the respective blanking apertures of the second columns of the first stage and of the second alignment rows of the sets thereof of the array, and selectively individually enabling the aligned blanking apertures the array in accordance with the desired pattern of the first target positions of the first row of the object, and repeating the second substep for each of the successive columns and alignment rows of the first stage of the array;

in each of second and successive steps and, for each step, in each of the associated first and successive substeps, moving the object relative to the array in the first direction and scanning the array to expose a desired pattern of the target positions on the object, for each of the plural columns of each of the plural and successive respective stages of plural columns of blanking apertures in each of the successive steps and for each of the first and successive respective alignment rows of blanking apertures and target positions of the plural sets thereof in each of the respective, successive substeps of each successive step.

32. A charge particle beam exposure system for producing a pattern on a surface of an object, comprising:

charge particle beam generating beams for generating a charge particle beam;

blanking aperture array means, having a plurality of selectively and individually controllable blanking apertures arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns to form a blanking aperture array, for shaping the charge particle beam generated by the charge particle beam generating means;

scanning means for repeatedly scanning the blanking aperture array means with the beam and for selectively controlling and thereby enabling the individual apertures thereof thereby to permit the scanning beam to pass through the individual, selectively enabled apertures of the array;

holding means for holding an object to be exposed;

deflecting means for deflecting the scanning beam, after passing through a selectively enable aperture of the blanking aperture array means to scan the object in a corresponding position thereon;

means for defining potential target positions to be exposed on the object, the target positions are arranged in a two dimensional configuration of parallel rows and transverse, parallel columns corresponding to the two-dimensional configuration of the blanking apertures of the blanking aperture array means;

means for moving the object, as held by the holding means, relative to the blanking aperture array means and in a first direction parallel to the respective columns of the blanking aperture array and of the target positions and for performing;

a first step of scanning the blanking aperture array to expose a desired pattern of first target positions in a first row on the object with the beam in accordance with selectively enabling the corresponding apertures of the first row of apertures of the blanking aperture array means, and

a second step of moving the object relative to the blanking aperture array means in the first direction so as to position the first potential target positions on the object in correspondence with a second, next excessive row of apertures of the array and thereby to position a second row of potential target positions on the object with the first row of apertures of the array and selectively and individually enabling the blanking apertures of the second row of the blanking aperture array in accordance with the desired pattern of the first target positions of the first row of the object and, simultaneously, selectively and individually enabling the apertures of the first row of the array in accordance with a desired pattern of second target position in a second row on the object, and scanning the blanking aperture array with the beam so as to expose the desired pattern of first target positions in the first row and the second target positions in the second row of the object with the beam, in accordance with the selectively enabled and corresponding apertures of the respective, second and first rows of apertures of the blanking aperture array.

33. An apparatus for exposing an object by a charged particle beam exposure system having means for generating a charge particle beam, a blanking aperture array comprising a plurality of selectively and individually controllable blanking apertures arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns, and means for repeatedly scanning the blanking aperture array with the beam and for selectively controlling and thereby enabling the individual apertures thereof thereby to permit the scanning beam to pass through the individual, selectively enabled apertures of the array, means for holding an object to be exposed and deflecting means for deflecting the beam, after passing through a selectively enabled aperture of the array, to scan the object in a corresponding target position thereon, said method comprising:

means for defining the respective positions of the blanking apertures within the blanking aperture array and in accordance with two-dimensional configuration of parallel rows and transverse, parallel columns, the columns being grouped in parallel stages and each stage comprising a set of a common number of plural columns including a first and successive columns, the respectively corresponding apertures of the set of successive columns of each of the plurality of stages being successively spaced and off-set in the column direction and the respective blanking apertures of the respective, first and successive columns of sets thereof, of the plural stages, being aligned in respective rows of a row alignment pattern, the row alignment pattern thereby including plural sets, each set comprising a number of first and successive alignment rows equal to the common number of the columns of apertures in each of the plural stages;

means for defining potential target positions to be exposed on the object, the target positions being arranged in a two-dimensional configuration of parallel rows and transverse, parallel columns corresponding to the two-dimensional configuration of the array and including plural, adjacent target positions in each of the plural columns arranged in respectively corresponding target position rows and grouped in sets of, each of plural rows, the plural sets of target position rows respectively corresponding the plural sets of blanking aperture alignment rows and the first and successive target position rows of each set respectively corresponding to the first and successive alignment rows of the array; and

means for moving the object relative to the blanking aperture array in a succession of steps, each step including a set of plural substeps comprising a first and successive substeps equal in number to the number of first and successive columns in each stage of plural columns of the blanking aperture array and thereby in a first step and associated first substep, scanning the blanking aperture array to expose a desired pattern of first target positions in the corresponding first row alignment position of the plural sets thereof and in a first column of target positions on the object with the beam, in accordance with selectively enabling the corresponding apertures of the first alignment row of apertures of the first column thereof, of the blanking aperture array and for moving;

in a second substep of the first step, the object relative to the array in the first direction in so as to position the second alignment row of each of the plural sets thereof of potential target group positions of the first column on the object with the target column of potential target positions respectively of the second alignment rows of the sets of the array, and selectively individually enabling the aligned blanking apertures of the array in accordance with the desired pattern of the first target positions of the first row of the object, and repeating the second substeps for each of the successive columns and alignment rows of the first stage of the array, and

in each of second and successive steps and, for each step, in each of the associated first and successive steps, moving the object relative to the array in the first direction and scanning the array to expose a desired pattern of the target positions on the object, for each of the plural columns of each of the plural and successive respective stages of plural columns of blanking apertures in each of the successive steps and for each of the first and successive respective alignment rows of blanking apertures and target positions of the plural sets thereof in each of the respective successive substeps of each successive step.