Method for manufacturing semiconductor device

• US 20050245007A1
• Filed: 06/23/2005
• Published: 11/03/2005
• Est. Priority Date: 12/28/2001
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Isobe, Atsuo, Shibata, Hiroshi, Shiga, Aiko, Yamazaki, Shunpei, Azami, Munehiro, Kokubo, Chiho
• Granted Patent: US 7,129,121 B2
• Time in Patent Office: Days
• US Class Current: 438/150
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02422 Non-crystalline insulating materials, e.g. glass, polymers
• CPC Class Codes: H01L 21/02425 Conductive materials, e.g. metallic silicides
• CPC Class Codes: H01L 21/02488 Insulating materials
• CPC Class Codes: H01L 21/02496 Layer structure
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02609 Crystal orientation
• CPC Class Codes: H01L 21/02672 using crystallisation enhancing elements
• CPC Class Codes: H01L 21/02678 Beam shaping, e.g. using a mask
• CPC Class Codes: H01L 21/02683 Continuous wave laser beam
• CPC Class Codes: H01L 21/02686 Pulsed laser beam
• CPC Class Codes: H01L 21/02691 Scanning of a beam
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1281 by using structural features to control crystal growth, e.g. placement of grain filters
• CPC Class Codes: H01L 27/1285 using control of the annealing or irradiation parameters, e.g. using different scanning direction or intensity for different transistors
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/66757 Lateral single gate single channel transistors with non-inverted structure, i.e. the channel layer is formed before the gate
• CPC Class Codes: H01L 29/66765 Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate
• CPC Class Codes: H01L 29/78603 : characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78621 : with LDD structure or an extension or an offset region or characterised by the doping profile
• CPC Class Codes: H01L 29/78675 : with normal-type structure, e.g. with top gate

Abstract

A method for manufacturing a semiconductor device having steps of forming an amorphous semiconductor on a substrate having an insulating surface; patterning the amorphous semiconductor to form plural first island-like semiconductors; irradiating a linearly condensed laser beam on the plural first island-like semiconductors while relatively scanning the substrate, thus crystallizing the plural first island-like semiconductors; patterning the plural first island-like semiconductors that have been crystallized to form plural second island-like semiconductors; forming plural transistors using the plural second island-like semiconductors; and forming a unit circuit using a predetermined number of the transistors, where the second island-like semiconductors used for the predetermined number of the transistors are formed from the first island-like semiconductors that are different from each other.

Claims

1. A method for manufacturing a semiconductor device comprising:

forming an insulating film having plural projections over a substrate;

forming a first film comprising amorphous semiconductor over the insulating film and at least between the projections;

heating the first film for improving crystallinity of the first film comprising amorphous semiconductor, thereby producing a second film comprising crystalline semiconductor;

etching the second film comprising crystalline semiconductor, thereby forming plural third films comprising crystalline semiconductor;

irradiating the plural third film comprising crystalline semiconductor with a laser beam having a linear shape with changing a position of the substrate relative to the laser beam for improving crystallinity of the plural third films, thereby producing a plural fourth films comprising crystalline semiconductor;

etching the plural fourth films comprising crystalline semiconductor for forming plural fifth films comprising crystalline semiconductor from the plural fourth films; and

forming a circuit comprising plural transistors from at least a part of the plural fifth films comprising crystalline semiconductor,

wherein at least the part of the fifth films are obtained from at least two of the fourth films.

2. A method of manufacturing a semiconductor device according to claim 1, further comprising forming a layer containing a metal element over the first film comprising amorphous semiconductor before heating the first film.

3. The method for manufacturing a semiconductor device according to claim 1, wherein the plural transistors are arranged so that all directions of migration of electric charges in their channel forming regions are substantially parallel to each other.

4. The method for manufacturing a semiconductor device according to claim 1, wherein directions of migration of electric charges in channel forming regions of the plural transistors are parallel to the direction of changing a position of the substrate relative to the laser beam.

5. The method for manufacturing a semiconductor device according to claim 1, wherein the plural transistors are connected in parallel.

6. The method for manufacturing a semiconductor device according to claim 1, wherein the laser beam is oscillated from a continuous wave laser apparatus.

7. The method for manufacturing a semiconductor device according to claim 1, wherein the laser beam is oscillated from a continuous wave laser selected from a YAG laser, a YVO₄ laser, a YLF laser, a YAIO₃ laser, a glass laser, a ruby laser, an alexandrite laser, and a Ti:

sapphire laser.

8. The method for manufacturing a semiconductor device according to claim 1, wherein the laser beam is oscillated from a laser selected from a continuous wave excimer laser, an Ar laser, a Kr laser, and a CO₂ laser.

9. The method for manufacturing a semiconductor device according to claim 1, wherein the laser beam is oscillated from a laser selected from a continuous wave helium cadmium laser, a copper vapor laser, and a gold vapor laser.