SUBSTRATE PROCESSING APPARATUS

• US 20070190746A1
• Filed: 03/23/2007
• Published: 08/16/2007
• Est. Priority Date: 05/21/2003
• Status: Abandoned Application

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ito, Masataka, Tsuboi, Takashi, Miyabayashi, Hiroshi, Yamagata, Kenji, Moriwaki, Ryuji, Takanashi, Kazuhito, Kakizaki, Yasuo
• Application Number:
  US11/690,395
• Publication Number:
  US 20070190746A1
• Time in Patent Office: Days
• US Class Current: 438/455
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02238 silicon in uncombined form, i.e. pure silicon
• CPC Class Codes: H01L 21/30604 Chemical etching
• CPC Class Codes: H01L 21/31056 the removal being a selective chemical etching step, e.g. selective dry etching through a mask
• CPC Class Codes: H01L 21/31654 of semiconductor materials, e.g. the body itself
• CPC Class Codes: H01L 21/32134 by liquid etching only
• CPC Class Codes: H01L 21/6708 using mainly spraying means, e.g. nozzles
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond
• CPC Class Codes: H01L 21/76259 with separation/delamination along a porous layer
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

An SOI substrate which has a thick SOI layer is first prepared. Then, the SOI layer is thinned to a target film thickness using as a unit a predetermined thickness not more than that of one lattice. This thinning is performed by repeating a unit thinning step which includes an oxidation step of oxidizing the surface of the SOI layer by the predetermined thickness not more than that of one lattice and a removal step of selectively removing silicon oxide formed by the oxidation. The SOI layer of the SOI substrate is chemically etched by supplying a chemical solution to the SOI layer, and the film thickness of the etched SOI layer is measured. When the measured film thickness of the SOI layer has a predetermined value, a process of chemically etching the SOI layer ends.

Claims

1. A substrate processing apparatus suitable for processing a substrate, which has a silicon layer on a insulating layer, the apparatus comprising:

an oxidizing agent supply mechanism, which supplies an oxidizing agent to the substrate to oxidize a surface of the silicon layer;

an etchant supply mechanism, which supplies to the substrate an etchant for selectively etching silicon oxide to selectively remove silicon oxide formed on the surface of the silicon layer; and

a controller, which controls the oxidizing agent supply mechanism and the etchant supply mechanism so as to repeat a unit thinning step of thinning the silicon layer by oxidizing the surface of the silicon layer to form the silicon oxide and selectively removing the silicon oxide.

2. The apparatus according to claim 1, wherein the controller is configured to control repetition of the unit thinning step such that the silicon layer is thinned to a desired thickness.

3. The apparatus according to claim 1, further comprising a measurement unit, which measures a thickness of the silicon layer, wherein the controller is configured to stop repeating the thinning step when it is determined on the basis of a measurement result from the measurement unit that the silicon layer is thinned to a desired thickness.

4. The apparatus according to claim 1, further comprising a measurement unit, which measures a thickness of the silicon layer,

wherein the controller is configured to determine a repetition count of the thinning step required to thin the silicon layer to a desired thickness on the basis of a measurement result from the measurement unit.

5. A substrate processing apparatus comprising:

an etching device, which chemically etches a semiconductor layer of a semiconductor substrate by supplying a chemical to the semiconductor layer;

a film thickness measurement device, which measures a thickness of the semiconductor layer; and

a control unit, which ends a process of chemically etching the semiconductor layer on the basis of a measurement result from the film thickness measurement device.

7. The apparatus according to claim 5, wherein the control unit has a mechanism, which stops a process of supplying a chemical to the semiconductor layer.

8. The apparatus according to claim 7, wherein the control unit further comprises a mechanism, which supplies a rinse to the semiconductor layer.

9. The apparatus according to claim 8, wherein the control unit further comprises a mechanism, which rotates the semiconductor substrate.

10. The apparatus according to claim 5, wherein the film thickness measurement device comprises:

an irradiator, which irradiates a surface of the semiconductor layer with one of light, X-rays, and ultrasonic waves;

a measurement unit, which measures the one of light, X-rays, and ultrasonic waves reflected on the surface of the semiconductor layer; and

a converter, which converts a measurement result from the measurement unit into the film thickness of the semiconductor layer.

11. The apparatus according to claim 5, wherein the film thickness measurement device comprises:

a measurement unit, which measures concentrations of components of the semiconductor layer contained in a chemical solution, which is used to etch the semiconductor layer; and

a converter, which converts a measurement result from the measurement unit into the film thickness of the semiconductor layer.

12. The apparatus according to claim 5, wherein the film thickness measurement device comprises:

a measurement unit, which measures a weight of the semiconductor substrate; and

a converter, which converts a measurement result from the measurement unit into the film thickness of the semiconductor layer.

13. The apparatus according to claim 5, further comprising a cover member arranged so as to surround a region in which the substrate is arranged.

6. A substrate processing apparatus comprising:

a holder, which holds a semiconductor substrate;

a chemical solution supply device, which has a nozzle arranged above the holder and supplies a chemical solution for chemically etching a semiconductor layer of the semiconductor substrate held by the holder from the nozzle to the semiconductor layer while an entire surface of the semiconductor layer is exposed;

a film thickness measurement device, which measures a film thickness of the semiconductor layer; and

a control unit, which ends a process of chemically etching the semiconductor layer on the basis of a measurement result from the film thickness measurement device.