METHOD FOR MANUFACTURING MICROCRYSTALLINE SEMICONDUCTOR FILM AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

• US 20110053358A1
• Filed: 08/20/2010
• Published: 03/03/2011
• Est. Priority Date: 08/25/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: OHTSUKI, Takashi, KURIKI, Kazutaka, YOKOI, Tomokazu, ENDO, Toshiya, TAJIMA, Ryota, ICHIJO, Mitsuhiro, YAMAZAKI, Shunpei, TOKUMARU, Ryo, TANAKA, Tetsuhiro, TORIUMI, Satoshi
• Granted Patent: US 8,252,669 B2
• Time in Patent Office: Days
• US Class Current: 438/488
• CPC Class Codes: C23C 16/24 Deposition of silicon only
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/45574 Nozzles for more than one gas
• CPC Class Codes: C23C 16/5096 Flat-bed apparatus
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: H01J 37/32541 Shape
• CPC Class Codes: H01J 37/32834 Exhausting
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• 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 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

An object of one embodiment of the present invention is to provide a technique for manufacturing a dense crystalline semiconductor film (e.g., a microcrystalline semiconductor film) without a cavity between crystal grains. A plasma region is formed between a first electrode and a second electrode by supplying high-frequency power of 60 MHz or less to the first electrode under a condition where a pressure of a reactive gas in a reaction chamber of a plasma CVD apparatus is set to 450 Pa to 13332 Pa, and a distance between the first electrode and the second electrode of the plasma CVD apparatus is set to 1 mm to 20 mm; crystalline deposition precursors are formed in a gas phase including the plasma region; a crystal nucleus of 5 nm to 15 nm is formed by depositing the deposition precursors; and a microcrystalline semiconductor film is formed by growing a crystal from the crystal nucleus.

Claims

1. A method for manufacturing a microcrystalline semiconductor film, comprising the steps of:

forming a plasma region between a first electrode and a second electrode by supplying high-frequency power of 60 MHz or less to the first electrode under a condition where a pressure of a reactive gas in a reaction chamber of a plasma CVD apparatus is set to greater than or equal to 450 Pa and less than or equal to 13332 Pa, and a distance between the first electrode and the second electrode of the plasma CVD apparatus is set to greater than or equal to 1 mm and less than or equal to 20 mm;

forming crystalline deposition precursors in a gas phase including the plasma region;

forming a crystal nucleus of greater than or equal to 5 nm and less than or equal to 15 nm by depositing the crystalline deposition precursors over a substrate; and

forming a microcrystalline semiconductor film by growing a crystal from the crystal nucleus.

2. The method for manufacturing a microcrystalline semiconductor film according to claim 1, wherein an electron temperature in the plasma region is reduced and an electron density in the plasma region is increased by adding a rare gas to the reactive gas, so that crystallinity of the microcrystalline semiconductor film is improved.

3. The method for manufacturing a microcrystalline semiconductor film according to claim 1, further comprising the steps of

forming a gate electrode over the substrate;

forming a gate insulating layer over the gate electrode;

forming the microcrystalline semiconductor layer over the gate insulating layer; and

forming a wiring electrically connected to the microcrystal line semiconductor layer.

4. A method for manufacturing a microcrystalline semiconductor film, using a plasma CVD apparatus provided with a first electrode and a second electrode in a reaction chamber, comprising the steps of:

introducing a reactive gas into the reaction chamber through a gas supply port in the first electrode provided with a plurality of projected portions;

setting a pressure of the reaction chamber to greater than or equal to 450 Pa and less than or equal to 13332 Pa;

setting a distance between the first electrode and the second electrode to greater than or equal to 1 mm and less than or equal to 20 mm;

forming a plasma region between the first electrode and the second electrode by supplying high-frequency power of 60 MHz or less to the first electrode;

forming crystalline deposition precursors including a semiconductor in a gas phase including the plasma region;

forming a crystal nucleus of greater than or equal to 5 nm and less than or equal to 15 nm by depositing the crystalline deposition precursors over a substrate; and

forming a microcrystalline semiconductor film by growing a crystal from the crystal nucleus.

5. The method for manufacturing a microcrystalline semiconductor film according to claim 4, wherein the gas supply port is provided between the plurality of projected portions.

6. The method for manufacturing a microcrystalline semiconductor film according to claim 4, wherein the gas supply port is provided on an apex of the plurality of projected portions.

7. The method for manufacturing a microcrystalline semiconductor film according to claim 4, wherein an electron temperature in the plasma region is reduced and an electron density in the plasma region is increased by adding a rare gas to the reactive gas, so that crystallinity of the microcrystalline semiconductor film is improved.

8. The method for manufacturing a microcrystalline semiconductor film according to claim 4, further comprising the steps of

forming a gate electrode over the substrate;

forming a gate insulating layer over the gate electrode;

forming the microcrystalline semiconductor layer over the gate insulating layer; and

forming a wiring electrically connected to the microcrystalline semiconductor layer.

9. A method for manufacturing a microcrystalline semiconductor film, using a plasma CVD apparatus provided with an upper electrode and a lower electrode in a reaction chamber, comprising the steps of:

introducing a reactive gas into the reaction chamber;

setting a pressure of the reaction chamber to greater than or equal to 450 Pa and less than or equal to 13332 Pa;

forming a plasma region between the upper electrode and the lower electrode by supplying high-frequency power of 60 MHz or less to the upper electrode;

forming crystalline deposition precursors in a gas phase including the plasma region;

forming a crystal nucleus of greater than or equal to 5 nm and less than or equal to 15 mm by depositing the crystalline deposition precursors over a substrate; and

growing a crystal from the crystal nucleus,

wherein the upper electrode comprises;

a plurality of projected portions for forming glow discharge plasma in the reaction chamber by supplying the high-frequency power;

a first gas supply port provided on an apex of the plurality of projected portions; and

a second gas supply port provided between the plurality of projected portions,

wherein the plurality of projected portions have a tapered shape and are chamfered, and

wherein a distance between the upper electrode and the lower electrode is greater than or equal to 1 mm and less than or equal to 20 mm.

10. The method for manufacturing a microcrystalline semiconductor film according to claim 9, wherein an electron temperature in the glow discharge plasma is reduced and an electron density in the glow discharge plasma is increased by adding a rare gas to the reactive gas, so that crystallinity of the microcrystalline semiconductor film is improved.

11. The method for manufacturing a microcrystalline semiconductor film according to claim 9, further comprising the steps of

forming a gate electrode over the substrate;

forming a gate insulating layer over the gate electrode;

forming the microcrystalline semiconductor layer over the gate insulating layer; and

forming a wiring electrically connected to the microcrystalline semiconductor layer.

12. A plasma CVD apparatus comprising:

a reaction chamber;

a first electrode and a second electrode facing each other in the reaction chamber, wherein a substrate is configured to be placed over the second electrode, and

wherein the first electrode comprises;

a plurality of projected portions for forming glow discharge plasma in the reaction chamber; and

a gas supply port provided between the plurality of projected portions,

wherein the plurality of projected portions has a tapered shape and is chamfered.

13. A plasma CVD apparatus comprising:

a reaction chamber;

a first electrode and a second electrode facing each other in the reaction chamber, wherein a substrate is configured to be placed over the second electrode, and

wherein the first electrode comprises;

a plurality of projected portions for forming glow discharge plasma in the reaction chamber; and

a gas supply port provided on an apex of the plurality of projected portions,

wherein the plurality of projected portions has a tapered shape and is chamfered.

14. A plasma CVD apparatus comprising:

a reaction chamber;

an upper electrode and a lower electrode facing each other in the reaction chamber, wherein a substrate is configured to be placed over the lower electrode, and

wherein the upper electrode comprises;

a plurality of projected portions for forming glow discharge plasma in the reaction chamber;

a first gas supply port provided on an apex of the plurality of projected portions; and

a second gas supply port provided between the plurality of projected portions,

wherein the plurality of projected portions has a tapered shape and is chamfered.