Semiconductor thin film and semiconductor device

• US 6,087,679 A
• Filed: 07/22/1998
• Issued: 07/11/2000
• Est. Priority Date: 07/23/1997
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Ohtani, Hisashi, Ogata, Yasushi, Yamazaki, Shunpei, Miyanaga, Akiharu, Mitsuki, Toru
• Primary Examiner(s): Meier, Stephen D.
• Application Number:
  US09/120,290
• Time in Patent Office: 720 Days
• Field of Search: 257/64, 257/65, 257/66
• US Class Current: 257/65
• CPC Class Codes: G02F 1/13454 Drivers integrated on the active matrix substrate G02F1/136277 takes precedence
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02592 amorphous
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H01L 21/02667 Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth
• CPC Class Codes: H01L 21/02672 using crystallisation enhancing elements
• CPC Class Codes: H01L 21/3221 of silicon bodies, e.g. for gettering
• CPC Class Codes: H01L 21/8221 Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1277 using a crystallisation promoting species, e.g. local introduction of Ni catalyst
• CPC Class Codes: H01L 29/04 characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes characterised by physical imperfections H01L29/30
• 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 29/78654 Monocrystalline silicon transistors
• CPC Class Codes: H01L 29/78675 with normal-type structure, e.g. with top gate
• CPC Class Codes: Y10S 438/973 Substrate orientation

Abstract

After an amorphous semiconductor thin film is crystallized by utilizing a catalyst element, the catalyst element is removed by performing a heat treatment in an atmosphere containing a halogen element. A resulting crystalline semiconductor thin film exhibits {110} orientation. Since individual crystal grains have approximately equal orientation, the crystalline semiconductor thin film has substantially no grain boundaries and has such crystallinity as to be considered a single crystal or considered so substantially.

Claims

1. A semiconductor thin film comprising a collected body of a plurality of rod-like or flat-rod-like crystals each comprising silicon as a main component, wherein a main orientation plane substantially coincides with a {110} plane,

wherein a concentration, in the semiconductor thin film, of each of carbon and nitrogen is 5×

10¹⁷ atoms/cm³ or less and a concentration of oxygen is 1×

10¹⁸ atoms/cm³ or less, respectively, and

wherein the rod-like or flat-rod-like crystals contact each other while forming rotation angles having absolute values that are within 3°

.

2. The semiconductor thin film according to claim 1,

wherein an electron beam diffraction pattern of the semiconductor thin film has particular regularity due to {110} orientation,

wherein each of diffraction spots of the electron beam diffraction pattern is substantially circular, and

wherein a ratio of a minor-axis length to a major-axis length of each of the diffraction spots is in a range of 1/1 to 1/1.5.

3. The semiconductor thin film according to claim 1,

wherein an electron beam diffraction pattern of the semiconductor thin film has particular regularity due to {110} orientation,

wherein each of diffraction spots of the electron beam diffraction pattern has a spread that is on a concentric circle having a center at a central point of an electron beam irradiation area, and

wherein a tangential line to each of the diffraction spot from the central point of the electron beam irradiation area and a line segment connecting the central point of the electron beam irradiation area and a central point of the diffraction spot form an angle that is within ±

1.5°

.

4. The semiconductor thin film according to claim 1, wherein the semiconductor thin film is formed on an undercoat insulating layer in which an average of height differences between recesses and protrusions is 5 nm or less.

5. A semiconductor device comprising a semiconductor film having at least a channel forming region, said semiconductor film comprising a collected body of a plurality of rod-like or flat-rod-like crystals each having silicon as a main component,

wherein a main orientation plane of the semiconductor thin film substantially coincides with a {110} plane,

wherein a concentration, in the semiconductor thin film, of each of carbon and nitrogen is 5×

10¹⁷ atoms/cm³ or less and a concentration of oxygen is 1×

10¹⁸ atoms/cm³ or less, and

wherein the rod-like or flat-rod-like crystals contact each other while forming rotation angles having absolute values that are within 3°

.

6. The device according to claim 5 wherein said semiconductor device is an apparatus selected from the group consisting of a video camera, an electronic still camera, a projector, a head-mounted display, a car navigation apparatus, a personal computer, and a portable information terminal apparatus.

7. The semiconductor device according to claim 5,

wherein an electron beam diffraction pattern of the semiconductor thin film has particular regularity due to {110} orientation,

wherein each of diffraction spots of the electron beam diffraction pattern is approximately circular, and

wherein a ratio of a minor-axis length to a major-axis length of each of the diffraction spots is in a range of 1/1 to 1/1.5.

8. The device according to claim 7 wherein said semiconductor device is an apparatus selected from the group consisting of a video camera, an electronic still camera, a projector, a head-mounted display, a car navigation apparatus, a personal computer, and a portable information terminal apparatus.

9. The semiconductor device according to claim 5,

wherein an electron beam diffraction pattern of the semiconductor thin film has particular regularity due to {110} orientation,

wherein each of diffraction spots of the electron beam diffraction pattern has a spread that is on a circle having a center at a central point of an electron beam irradiation area, and

wherein a tangential line to each of the diffraction spot from the central point of the electron beam irradiation area and a line segment connecting the central point of the electron beam irradiation area and a central point of the diffraction spot form an angle that is within ±

1.5°

.

10. A semiconductor device comprising the semiconductor device according to claim 9 and being an apparatus selected from the group consisting of a video camera, an electronic still camera, a projector, a head-mounted display, a car navigation apparatus, a personal computer, and a portable information terminal apparatus.

11. The semiconductor device according to claim 5, wherein the semiconductor thin film is formed on an undercoat insulating layer in which an average of height differences between recesses and protrusions is 5 nm or less.

12. The device according to claim 11 wherein said semiconductor device is an apparatus selected from the group consisting of a video camera, an electronic still camera, a projector, a head-mounted display, a car navigation apparatus, a personal computer, and a portable information terminal apparatus.

13. The semiconductor device according to claim 12, wherein the portable information terminal apparatus is an apparatus selected from the group consisting of a mobile computer, a cellular telephone, and a PHS telephone.

14. A semiconductor device comprising a semiconductor thin film having a main orientation plane substantially coinciding with a {110} plane,

wherein a concentration, in the semiconductor thin film, of each of carbon and nitrogen is 5×

10¹⁷ atoms/cm³ or less and a concentration of oxygen is 1×

10¹⁸ atoms/cm³ or less, respectively,

wherein an electron beam diffraction pattern of the semiconductor thin film has particular regularity due to {110} orientation,

wherein each of diffraction spots of the electron beam diffraction pattern is substantially circular, and

wherein a ratio of a minor-axis length to a major-axis length of each of the diffraction spots is in a range of 1/1 to 1/1.5.

15. The device according to claim 14, wherein the semiconductor thin film is formed on an undercoat insulating layer in which an average of height differences between recesses and protrusions is 5 nm or less.

16. A semiconductor device comprising a semiconductor thin film comprising a main orientation plane substantially coinciding with a {110} plane,

wherein a concentration, in the semiconductor thin film, of each of carbon and nitrogen is 5×

10¹⁷ atoms/cm³ or less and a concentration of oxygen is 1×

10¹⁸ atoms/cm³ or less, respectively,

wherein an electron beam diffraction pattern of the semiconductor thin film has particular regularity due to {110} orientation,

wherein each of diffraction spots of the electron beam diffraction pattern has a spread that is on a concentric circle having a center at a central point of an electron beam irradiation area, and

wherein a tangential line to each of the diffraction spot from the central point of the electron beam irradiation area and a line segment connecting the central point of the electron beam irradiation area and a central point of the diffraction spot form an angle that is within ±

1.5°

.

17. The device according to claim 16, wherein the semiconductor thin film is formed on an undercoat insulating layer in which an average of height differences between recesses and protrusions is 5 nm or less.