Solar cell

Patent metadata

Field	Value
Publication number	US-2015129037-A1
Application number	US-201414536270-A
Country	US
Kind code	A1
Filing date	Nov 7, 2014
Priority date	Nov 8, 2013
Publication date	May 14, 2015
Grant date	—

Abstract

A solar cell is discussed. The solar cell according to an embodiment includes a photoelectric conversion unit including a first conductive type region and a second conductive type region formed on the same side of the photoelectric conversion unit; and an electrode formed on the photoelectric conversion unit and including an adhesive layer formed on the photoelectric conversion unit and an electrode layer formed on the adhesive layer, wherein the adhesive layer has a coefficient of thermal expansion that is greater than a coefficient of thermal expansion of the photoelectric conversion unit and is less than a coefficient of thermal expansion of the electrode layer.

First claim

What is claimed is:

1 . A solar cell comprising:
a photoelectric conversion unit comprising a first conductive type region and a second conductive type region formed on the same side of the photoelectric conversion unit; and an electrode formed on the photoelectric conversion unit and comprising an adhesive layer formed on the photoelectric conversion unit and an electrode layer formed on the adhesive layer, wherein the adhesive layer has a coefficient of thermal expansion that is greater than a coefficient of thermal expansion of the photoelectric conversion unit and is less than a coefficient of thermal expansion of the electrode layer.

2 . The solar cell of claim 1 , wherein the coefficient of thermal expansion of the adhesive layer is greater than coefficients of thermal expansion of both the first conductive type region and the second conductive type region.

3 . The solar cell according to claim 1 , wherein the adhesive layer has transparency.

4 . The solar cell according to claim 1 , wherein the adhesive layer comprises a metal.

5 . The solar cell according to claim 4 , wherein the adhesive layer comprises titanium (Ti) or tungsten (W).

6 . The solar cell according to claim 1 , wherein the electrode layer comprises a plurality of layers, and the adhesive layer has a smaller thickness than each of the plurality of layers of the electrode layer.

7 . The solar cell according to claim 1 , wherein the adhesive layer has a thickness of 50 nm or less.

8 . The solar cell according to claim 1 , wherein the photoelectric conversion unit includes at least one of a semiconductor substrate and a semiconductor layer, and
wherein the semiconductor substrate or the semiconductor layer comprises silicon (Si), and the portion of the electrode layer adjacent to the adhesive layer comprises at least one of copper (Cu), aluminum (Al), silver (Ag), gold (Au), and alloys thereof.

9 . The solar cell according to claim 1 , wherein the electrode layer comprises a first electrode layer disposed on the adhesive layer and comprising a reflective material and a second electrode layer formed on the first electrode layer and connected to a ribbon.

10 . The solar cell according to claim 9 , wherein the first electrode layer comprises at least one of Cu, Al, Ag, Au, and alloys thereof.

11 . The solar cell according to claim 10 , wherein a thickness ratio of the adhesive layer:the first electrode layer is between 1:2 and 1:60.

12 . The solar cell according to claim 9 , wherein the first electrode layer has a thickness of 50 nm to 300 nm.

13 . The solar cell according to claim 9 , wherein the second electrode layer comprises at least one of tin (Sn) and a nickel (Ni)-vanadium (V) alloy.

14 . The solar cell according to claim 13 , wherein the second electrode layer is formed by sputtering and has a thickness of 50 nm to 300 nm.

15 . The solar cell according to claim 13 , wherein the second electrode layer is formed by plating and has a thickness of 5 μm to 10 μm.

16 . The solar cell according to claim 9 , wherein the electrode layer further comprises a third electrode layer formed on the first electrode layer and disposed between the first and second electrode layers, the third electrode having a greater thickness than the first and second electrode layers, and the third electrode having a wider area than the first and second electrode layers.

17 . The solar cell according to claim 16 , wherein the third electrode layer is formed by plating and comprises Cu.

18 . The solar cell according to claim 16 , wherein the electrode layer further comprises a seed electrode layer disposed between the first electrode layer and the third electrode layer.

19 . The solar cell according to claim 18 , wherein the seed electrode layer is formed by sputtering and comprises Cu.

20 . A solar cell comprising:
a photoelectric conversion unit comprising a first conductive type region and a second conductive type region form on the same side of the photoelectric conversion unit; and an electrode formed on the photoelectric conversion unit and comprising an adhesive layer formed on the photoelectric conversion unit and an electrode layer formed on the adhesive layer, wherein the adhesive layer comprises titanium (Ti) or tungsten (W).

Assignees

• Lg Electronics Inc

Inventors

• Nam Jeongbeom
• Yang Doohwan
• Lee Eunjoo
• Jung Ilhyoung

Classifications

• Y02E10/52

  PV systems with concentrators · CPC title

• Y02E10/547

  Monocrystalline silicon PV cells · CPC title

• H10F10/146

  Back-junction photovoltaic cells, e.g. having interdigitated base-emitter regions on the back side · CPC title

• H10F19/908

  for back-contact photovoltaic cells · CPC title

• H10F77/122

  comprising only Group IV materials · CPC title