# US 10,312,400 B2 · Multi-junction solar cell

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,312,400 B2
- Document ID: US10312400B2
- Status: Granted
- Kind: B2
- Application number: 15/296,296
- Filed: 2016-10-18
- Published: 2017-02-09
- Granted: 2019-06-04
- Earliest claimed: 2014-10-02
- Assignees: International Business Machines Corporation
- Applicants: International Business Machines Corporation
- Inventors: Anirban Basu; Bahman Hekmatshoartabari; Davood Shahrjerdi
- Web page: https://patentgrep.com/patent/US10312400B2

## CPC

- H10F 71/121: {The active layers comprising only Group IV materials}
- H10F 10/142: comprising multiple PN homojunctions, e.g. tandem cells
- H10F 10/19: Photovoltaic cells having multiple potential barriers of different types, e.g. tandem cells having both PN and PIN junctions
- H10F 19/50: Integrated devices comprising at least one photovoltaic cell and other types of semiconductor or solid-state components (H10F19/75 takes precedence)
- H10F 77/122: comprising only Group IV materials
- H10F 77/1642: {including only Group IV materials}
- H10F 77/1662: {including only Group IV materials}
- Y02E 10/544: Solar cells from Group III-V materials
- Y02E 10/546: Polycrystalline silicon PV cells
- Y02E 10/547: Monocrystalline silicon PV cells
- Y02E 10/548: Amorphous silicon PV cells
- H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

A multi-junction solar cell comprising a high-crystalline silicon solar cell and a high-crystalline germanium solar cell. The high-crystalline silicon solar including a first p-doped layer and a n+ layer and the high-crystalline germanium solar cell including a second p layer and a heavily doped layer. The multi-junction solar cell can also be comprised of a heavily doped silicon layer on a non-light receiving back surface of the high-crystalline germanium solar cell and a tunnel junction between the high-crystalline silicon solar cell and the high-crystalline germanium solar cell.

## Claims

### Claim 1

A multi-junction solar cell comprising:
a crystalline silicon solar cell having an n-doped region and a silicon p-doped region, wherein:
the n-doped region is at a front surface of the crystalline solar cell, and
the silicon p-doped region is at a back surface of the crystalline solar cell;
a crystalline germanium solar cell having a germanium n+ layer and a germanium p-doped layer, wherein:
the germanium n+ layer is at a front surface of the crystalline germanium solar cell, and
the germanium p-doped layer is at a back surface of the crystalline germanium solar cell;
a p+ silicon layer formed on the back surface of the crystalline germanium solar cell;
a tunnel junction between the crystalline silicon solar cell and the crystalline germanium solar cell;
an SiO2 layer connected to a back surface of the p+ silicon layer; and
a monolithic circuit connected through the SiO2 layer to the germanium n+ layer, the monolithic circuit including at least one transistor connected to the SiO2 layer.

### Claim 2 (depends on 1)

The multi-junction solar cell of claim 1, wherein the n-doped region further includes:
a hydrogenated amorphous silicon layer; and
a silicon n+ layer.

### Claim 3 (depends on 1)

The multi-junction solar cell of claim 1, wherein the silicon p-doped region further includes a p+ layer at the back surface of the crystalline silicon solar cell.

### Claim 4 (depends on 3)

The multi-junction solar cell of claim 3, wherein the p+ layer at the back surface of the crystalline silicon solar cell is silicon.

### Claim 5 (depends on 3)

The multi-junction solar cell of claim 3, wherein the p+ layer at the back surface of the crystalline silicon solar cell is SiGe.

### Claim 6 (depends on 1)

The multi-junction solar cell of claim 1 wherein a III-V compound semiconductor is configured to connect the crystalline germanium solar cell to the monolithic circuit.