Method for forming deposited film and photovoltaic element

• US 7,501,305 B2
• Filed: 10/18/2007
• Issued: 03/10/2009
• Est. Priority Date: 10/23/2006
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Shimoda, Hiroshi, Okabe, Shotaro, Tsuzuki, Hidetoshi, Matsuda, Koichi, Takai, Yasuyoshi
• Primary Examiner(s): Mulpuri; Savitri
• Application Number:
  US11/874,352
• Publication Number:
  US 20080096305A1
• Time in Patent Office: 509 Days
• Field of Search: 438/5, 438/14, 438/7, 438/16, 438/57, 438/61, 438/62, 438/72, 438/83, 438 96- 98, 438/485, 438/486, 427/255.28
• US Class Current: 438/57
• CPC Class Codes: C23C 16/24 Deposition of silicon only
• CPC Class Codes: C23C 16/545 for coating elongated substrates
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring
• CPC Class Codes: H01L 31/03685 including microcrystalline silicon, uc-Si
• CPC Class Codes: H01L 31/03762 including only elements of Group IV of the Periodic Table
• CPC Class Codes: H01L 31/076 Multiple junction or tandem solar cells
• CPC Class Codes: H01L 31/1824 Special manufacturing methods for microcrystalline Si, uc-Si
• CPC Class Codes: H01L 31/202 including only elements of Group IV of the Periodic Table
• CPC Class Codes: Y02E 10/545 Microcrystalline silicon PV cells
• CPC Class Codes: Y02E 10/548 Amorphous silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method for forming a deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD includes forming a deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD under conditions such that when a deposited film having a thickness of 300 nm or more is formed on a substrate while the substrate is in a stationary state, an area of the microcrystalline silicon region in which an intensity of Raman scattering attributed to a crystalline substance in the deposited film is equal to or higher than three times an intensity of Raman scattering attributed to an amorphous is 50% or more of the total area based on the area of the microcrystalline silicon region and the area of a region composed of the amorphous.

Claims

1. A method for forming a deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD, the method comprising a step of:

forming a deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD under conditions such that when a deposited film having a thickness of 300 nm or more is formed on a substrate while the substrate is in a stationary state, an area of the microcrystalline silicon region in which an intensity of Raman scattering attributed to a crystalline substance in the deposited film is equal to or higher than three times an intensity of Raman scattering attributed to an amorphous is 50% or more of the total area based on the area of the microcrystalline silicon region and the area of a region composed of the amorphous, wherein the area of microcrystalline silicon region in which the intensity of Raman scattering attributed to the crystalline substance in the deposited film is equal to or higher than three times the intensity of Raman scattering attributed to amorphous is determined by color or reflectivity corresponding to microcrystalline silicon.

2. A method for forming a photovoltaic element including at least one pin junction by plasma-enhanced CVD on a moving substrate, at least one i-type layer being formed of a deposited film containing microcrystalline silicon, the method comprising a step of:

forming the deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD under conditions such that when a deposited film having a thickness of 300 nm or more is formed on a substrate while the substrate is in a stationary state, an area of the microcrystalline silicon region in which an intensity of Raman scattering attributed to a crystalline substance in the deposited film is equal to or higher than three times an intensity of Raman scattering attributed to an amorphous is 50% or more of the total area of the deposited film based on the area of the microcrystalline silicon region and the area of a region composed of the amorphous, wherein the area of microcrystalline silicon region in which the intensity of Raman scattering attributed to the crystalline substance in the deposited film is equal to or higher than three times the intensity of Raman scattering attributed to amorphous is determined by color or reflectivity corresponding to microcrystalline silicon.

3. A method for forming a deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD, the method comprising:

a first step of forming a deposited film while a substrate is being moved in plasma CVD;

a second step of forming a deposited film while the substrate is being moved; and

a third step of forming a deposited film while the substrate is in a stationary state, the third step being performed before the first step or between the first step and the second step,

wherein conditions for forming the deposited film while the substrate is being moved are controlled on the basis of the ratio of an area of the microcrystalline silicon region in which an intensity of Raman scattering attributed to a crystalline substance in the deposited film is equal to or higher than three times an intensity of Raman scattering attributed to an amorphous to the total area based on the area of the microcrystalline silicon region and the area of a region composed of the amorphous when the deposited film having a thickness of 300 nm or more is formed on the substrate while the substrate is in a stationary state in the third step.

4. A method for forming a deposited film containing microcrystalline silicon on a moving substrate by plasma-enhanced CVD, the method comprising:

a first step of forming a deposited film while a substrate is being moved in plasma CVD;

a second step of forming a deposited film while the substrate is being moved; and

a third step of forming a deposited film while the substrate is in a stationary state, the third step being performed before the first step or between the first step and the second step,

wherein the maintenance of a deposition-film-forming apparatus is performed on the basis of the ratio of an area of the microcrystalline silicon region in which an intensity of Raman scattering attributed to a crystalline substance in the deposited film is equal to or higher than three times an intensity of Raman scattering attributed to an amorphous to the total area based on the area of the microcrystalline silicon region and the area of a region composed of the amorphous when the deposited film having a thickness of 300 nm or more is formed on the substrate while the substrate is in a stationary state in the third step.