Solar cell

Patent metadata

Field	Value
Publication number	US-2016126368-A1
Application number	US-201514932755-A
Country	US
Kind code	A1
Filing date	Nov 4, 2015
Priority date	Nov 4, 2014
Publication date	May 5, 2016
Grant date	—

Abstract

A solar cell is discussed. The solar cell according to an embodiment includes a semiconductor substrate containing impurities of a first conductive type, a metal oxide layer positioned on the semiconductor substrate, an emitter region positioned on the metal oxide layer and having a second conductive type opposite the first conductive type, a first electrode connected to the emitter region, and a second electrode connected to the semiconductor substrate.

First claim

What is claimed is:

1 . A solar cell comprising:
a semiconductor substrate containing impurities of a first conductive type; a metal oxide layer positioned on the semiconductor substrate; an emitter region positioned on the metal oxide layer and having a second conductive type opposite the first conductive type; a first electrode connected to the emitter region; and a second electrode connected to the semiconductor substrate.

2 . The solar cell of claim 1 , wherein a metal included in the metal oxide layer includes at least one of a transition metal or a post-transition metal.

3 . The solar cell of claim 1 , wherein the metal oxide layer is formed of one of NiO, TiO 2 , HfO 2 , ZrO, WO, CuO, Ta 2 O 5 , and Al 2 O 3 .

4 . The solar cell of claim 1 , wherein the metal oxide layer and the emitter region are positioned on a back surface of the semiconductor substrate.

5 . The solar cell of claim 4 , further comprising a back surface field region positioned on the metal oxide layer and containing impurities of the first conductive type at a higher concentration than the impurities of the semiconductor substrate.

6 . The solar cell of claim 5 , wherein the emitter region and the back surface field region are formed of a polycrystalline silicon material.

7 . The solar cell of claim 5 , further comprising an intrinsic semiconductor layer positioned on a back surface of the metal oxide layer,
wherein the emitter region and the back surface field region are positioned to be separated from each other with the intrinsic semiconductor layer interposed therebetween.

8 . The solar cell of claim 5 , further comprising a tunnel layer positioned between the semiconductor substrate and the metal oxide layer and configured to pass through carriers produced in the semiconductor substrate, the tunnel layer being formed of a dielectric material.

9 . The solar cell of claim 8 , wherein a thickness of the metal oxide layer is greater than a thickness of the tunnel layer and is less than a thickness of the emitter region or a thickness of the back surface field region.

10 . The solar cell of claim 9 , wherein the thickness of the metal oxide layer is 5 nm to 50 nm.

11 . The solar cell of claim 1 , wherein when a voltage equal to or greater than a critical voltage is applied to front and back surfaces of the metal oxide layer, the metal oxide layer has a resistance equal to or less than 10Ω and greater than 0Ω, and
wherein when a voltage less than the critical voltage is applied to the front and back surfaces of the metal oxide layer or a voltage is not applied to the front and back surfaces of the metal oxide layer, the metal oxide layer has a resistance of 10 MΩ to 100 MΩ.

12 . The solar cell of claim 11 , wherein the critical voltage is 0.7V to 1V.

13 . The solar cell of claim 5 , wherein when the solar cell operates, carriers produced in the semiconductor substrate move through a first portion in the metal oxide layer between the semiconductor substrate and the emitter region and a second portion in the metal oxide layer between the semiconductor substrate and the back surface field region and does not move through a third portion in the metal oxide layer between the semiconductor substrate and the intrinsic semiconductor layer.

14 . The solar cell of claim 8 , wherein the dielectric material of the tunnel layer includes silicon carbide (SiCx) or silicon oxide (SiOx).

15 . The solar cell of claim 8 , wherein the tunnel layer has a thickness of 0.5 nm to 2.5 nm.

16 . The solar cell of claim 5 , further comprising a passivation layer positioned on back surfaces of the emitter region, the back surface field region, and the intrinsic semiconductor layer.

17 . The solar cell of claim 16 , wherein the passivation layer includes at least one of hydrogenated silicon nitride (SiNx:H), hydrogenated silicon oxide (SiOx:H), hydrogenated silicon nitride oxide (SiNxOy:H), hydrogenated silicon oxynitride (SiOxNy:H), or hydrogenated amorphous silicon (a-Si:H).

18 . A solar cell comprising:
a semiconductor substrate; an emitter region, a back surface field region, and an intrinsic region positioned on the semiconductor substrate; and a metal oxide layer positioned between the semiconductor substrate, the emitter region, the back surface field region, and the intrinsic region, wherein the metal oxide layer blocks a leakage current of the semiconductor substrate.

19 . The solar cell of claim 18 , wherein the metal oxide layer is formed of one of NiO, TiO 2 , HfO 2 , ZrO, WO, CuO, Ta 2 O 5 , and Al 2 O 3 .

20 . The solar cell of claim 18 , wherein the metal oxide layer has a thickness of 5 nm to 50 nm.

Assignees

• Lg Electronics Inc

Inventors

• Lee Yujin
• Chung Jin-Won

Classifications

• H10F77/1642

  including only Group IV materials · CPC title

• H10F77/219 Primary

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

• H10F77/14

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

• H10F77/12

  Active materials · CPC title

• H10F71/00

  Manufacture or treatment of devices covered by this subclass (patterning processes to connect thin photovoltaic cells in integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/33; manufacture or treatment of encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/80; manufacture or treatment of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) · CPC title