Solar cell

• US 10,720,537 B2
• Filed: 12/17/2018
• Issued: 07/21/2020
• Est. Priority Date: 03/17/2014
• Status: Active Grant

• Current Assignee: Shangrao Xinyuan Yuedong Technology Development Company Limited
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Chung, Indo, Shim, Seunghwan, Jung, Ilhyoung, Nam, Jeongbeom
• Primary Examiner(s): Mowla, Golam
• Application Number:
  US16/222,496
• Publication Number:
  US 20190115484A1
• Time in Patent Office: 582 Days
• CPC Class Codes: H01L 31/02167 for solar cells
• CPC Class Codes: H01L 31/02168 the coatings being antireflective or having enhancing optical properties for the solar cells
• CPC Class Codes: H01L 31/022433 Particular geometry of the grid contacts
• CPC Class Codes: H01L 31/022441 Electrode arrangements specially adapted for back-contact solar cells
• CPC Class Codes: H01L 31/0682 back-junction, i.e. rearside emitter, solar cells, e.g. interdigitated base-emitter regions back-junction cells
• CPC Class Codes: H01L 31/0747 comprising a heterojunction of crystalline and amorphous materials, e.g. heterojunction with intrinsic thin layer
• CPC Class Codes: H01L 31/1804 comprising only elements of Group IV of the Periodic Table
• CPC Class Codes: H01L 31/1868 Passivation
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

Discussed is a solar cell includes a semiconductor substrate, a conductive type region including a first conductive type region and a second conductive type region formed on one surface of the semiconductor substrate, an electrode including a first electrode and a second electrode, wherein the first electrode is connected to the first conductive type region and the second electrode is connected to the second conductive type region, and a passivation layer formed on the conductive type region. The passivation layer includes at least one of silicon nitride and silicon carbide.

Claims

1. A solar cell, comprising:

a semiconductor substrate including single-crystalline silicon;

a conductive type region comprising a first conductive type region and a second conductive type region formed on a back surface of the semiconductor substrate, the conductive type region including a polycrystalline silicon layer;

a first passivation layer comprising a silicon nitride layer formed on the conductive type region, and a silicon carbide layer formed on the silicon nitride layer;

an electrode comprising a first electrode and a second electrode, wherein the first electrode of a metal electrode being in contact with the polycrystalline silicon layer constituting the first conductive type region through a first opening penetrating the silicon nitride layer and the silicon carbide layer and the second electrode of a metal electrode being in contact with the polycrystalline silicon layer constituting the second conductive type region through a second opening penetrating the silicon nitride layer and the silicon carbide layer; and

an anti-reflection layer including silicon nitride on a front surface of the semiconductor substrate,

wherein a refractive index of the silicon nitride layer is larger than a refractive index of the anti-reflection layer.

2. The solar cell according to claim 1, wherein the refractive index of the silicon nitride layer is larger than a refractive index of the silicon carbide layer.

3. The solar cell according to claim 1, wherein the silicon nitride layer has a thickness that is the same as or larger than a thickness of the silicon carbide layer.

4. The solar cell according to claim 3, wherein a ratio of the thickness of the silicon carbide layer:

the thickness of the silicon nitride layer is about 1;

1 to about 1;

4.

5. The solar cell according to claim 1, wherein the silicon nitride layer has a thickness of about 50 nm to about 200 nm.

6. The solar cell according to claim 1, wherein the silicon carbide layer has a thickness of about 10 nm to about 50 nm.

7. The solar cell according to claim 1, further comprising a second passivation layer between the semiconductor substrate and the anti-reflection layer.

8. The solar cell according to claim 1, wherein the silicon carbide layer has a refractive index of about 1.5 to about 2.0.

9. The solar cell according to claim 1, wherein at least one of the first electrode and the second electrode comprises a plurality of metal layers formed by sputtering.

10. The solar cell according to claim 1, further comprising a tunneling layer between the back surface of the semiconductor substrate and the conductive type region.