Photoelectric conversion device

Patent metadata

Field	Value
Publication number	US-2016268458-A1
Application number	US-201415031834-A
Country	US
Kind code	A1
Filing date	Oct 24, 2014
Priority date	Oct 25, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

There is provided a photoelectric conversion device which can prevent the contact resistance between a non-crystalline semiconductor layer containing impurities and an electrode formed on the non-crystalline silicon layer from increasing, and can improve the element characteristics. A photoelectric conversion element ( 10 ) includes a silicon substrate ( 12 ), a first non-crystalline semiconductor layer ( 20 n ), a second non-crystalline semiconductor layer ( 20 p ), a first electrode ( 22 n ), and a second electrode ( 22 p ). One electrode ( 22 n ) includes first conductive layers ( 26 n, 26 p ), and second conductive layers ( 28 n, 28 p ). The first conductive layers ( 26 n, 26 p ) have a first metal as a main component. The second conductive layers ( 28 n, 28 p ) contain a second metal which is more likely to be oxidized than the first metal, are formed to be in contact with the first conductive layers ( 26 n, 26 p ), and are disposed to be closer to the silicon substrate ( 12 ) than the first conductive layers ( 26 n, 26 p ).

First claim

1 . A photoelectric conversion device comprising:
a semiconductor substrate; a first semiconductor layer having a first conductive type; a second semiconductor layer having a second conductive type opposite to the first conductive type; a first electrode which is formed on the first semiconductor layer; and a second electrode which is formed on the second semiconductor layer, wherein the first electrode includes a first conductive layer and a second conductive layer which is formed to be in contact with the first conductive layer, wherein the first conductive layer includes a first metal as a main component, and wherein the second conductive layer includes a second metal which is more likely to be oxidized than the first metal.

2 . The photoelectric conversion device according to claim 1 ,
wherein the second conductive layer is disposed between the first conductive layer and the first semiconductor layer.

3 . The photoelectric conversion device according to claim 2 ,
wherein the first electrode further includes a third conductive layer which is formed between the first semiconductor layer and the second conductive layer, and wherein the third conductive layer includes a third metal which is more unlikely to be oxidized than the second metal as a main component.

4 . The photoelectric conversion device according to claim 3 ,
wherein the first electrode further includes a fourth conductive layer which is formed to be in contact with the first semiconductor layer and the third conductive layer, and wherein the fourth conductive layer includes a fourth metal which is more likely to be oxidized than the third metal.

5 . The photoelectric conversion device according to claim 4 ,
wherein the fourth conductive layer contains an oxygen atom.

6 . The photoelectric conversion device according to claim 5 ,
wherein the maximum concentration of the oxygen atom in the fourth conductive layer is further on a side opposite to the semiconductor substrate than the center of the fourth conductive layer in the film thickness direction.

7 . The photoelectric conversion device according to claim 4 ,
wherein the fourth metal is more likely to be oxidized than a main component element of the first semiconductor layer.

8 . The photoelectric conversion device according to claim 1 ,
wherein the second conductive layer contains the oxygen atom.

9 . The photoelectric conversion device according to claim 8 ,
wherein the maximum concentration of the oxygen atom in the second conductive layer is further on the side opposite to the semiconductor substrate than the center of the second conductive layer in the film thickness direction.

10 . The photoelectric conversion device according to claim 1 ,
wherein the second metal is more likely to be oxidized than the main component element of the first semiconductor layer.

11 . The photoelectric conversion device according to claim 1 ,
wherein the first semiconductor layer includes a non-crystalline semiconductor.

12 . The photoelectric conversion device according to claim 11 ,
wherein the main component element of the first semiconductor layer is silicon, wherein the first metal is any of silver, platinum, and gold, and wherein the second metal is at least one of nickel, cobalt, iron, chrome, zinc, tantalum, manganese, titanium, aluminum, magnesium, cerium, niobium, molybdenum, and tungsten.

13 . The photoelectric conversion device according to claim 3 ,
wherein the main component element of the first semiconductor layer is silicon, wherein the first metal is any of silver, platinum, and gold, wherein the second metal is at least one of nickel, cobalt, iron, chrome, zinc, tantalum, manganese, titanium, aluminum, magnesium, cerium, niobium, molybdenum, and tungsten, and wherein the third metal is any of silver, platinum, and gold.

14 . The photoelectric conversion device according to claim 4 ,
wherein the main component element of the first semiconductor layer is silicon, wherein the first metal is any of silver, platinum, and gold, wherein the second metal is at least one of nickel, cobalt, iron, chrome, zinc, tantalum, manganese, titanium, aluminum, magnesium, cerium, niobium, molybdenum, and tungsten, wherein the third metal is any of silver, platinum, and gold, and wherein the fourth metal is at least one of nickel, cobalt, iron, chrome, zinc, tantalum, manganese, titanium, aluminum, magnesium, cerium, niobium, molybdenum, and tungsten.

15 . The photoelectric conversion device according to claim 1 ,
wherein the first conductive layer includes a plurality of metal crystal grains, and wherein the average crystal grain size of the metal crystal grains is greater than the thickness of the first conductive layer in the in-surface direction of the first conductive layer.

16 . The photoelectric conversion device according to claim 4 ,
wherein the third conductive layer includes a plurality of metal crystal grains, and wherein the average crystal grain size of the metal crystal grains is greater than the thickness of the third conductive layer in the in-surface direction of the third conductive layer.

17 . The photoelectric conversion device according to claim 15 ,
wherein, in the metal crystal grains, a crystal axis which is parallel to the thickness direction of the semiconductor substrate is preferentially oriented in the <111> direction.

18 . The photoelectric conversion device according to claim 1 ,
wherein the first conductive layer further contains tin.

Assignees

• Sharp Kk

Inventors

• Kimoto Kenji
• Koide Naoki
• ZOU Liumin
• Kobayashi Masamichi

Classifications

• Y02E10/547

  Monocrystalline silicon PV cells · CPC title

• H10F77/219

  Arrangements for electrodes of back-contact photovoltaic cells · CPC title

• H10F77/211

  for photovoltaic cells · CPC title

• H10F77/122

  comprising only Group IV materials · CPC title

• H10F77/14

  Shape of semiconductor bodies; Shapes, relative sizes or dispositions of semiconductor regions within semiconductor bodies · CPC title