Back to results
US 2022/0045225 A1Published application
Doped photovoltaic semiconductor layers and methods of making
AssigneeFirst Solar, Inc.
InventorsSachit Grover, Stuart Irvine, Xiaoping Li, Roger Malik, Shahram Seyedmohammadi, Gang Xiong, Wei Zhang
Life of this patent
Estimating the term…
Abstract
Provided are structures and methods for doping polycrystalline thin film semiconductor materials in photovoltaic devices. Embodiments include methods for forming and treating a photovoltaic semiconductor absorber layer.
Claims20
A method for treating a photovoltaic semiconductor absorber layer comprising:
- supplying a reducing agent to produce a reducing environment;
- contacting at least a portion of an absorber layer with a passivating agent while the absorber layer is in the reducing environment, wherein the absorber layer is doped with a group V dopant, and wherein the absorber layer comprises a II-VI semiconductor;
- and
- annealing the absorber layer with the passivating agent while in the reducing environment at a selected temperature and a selected pressure for a selected treatment duration, wherein the reducing environment comprises at least a trace amount of oxygen and a ratio of the partial pressure of the reducing agent to a partial pressure of the oxygen is at least 3.
1 more element
A method for forming a doped semiconductor absorber layer, comprising:
- disposing an absorber layer of a photovoltaic stack to form an absorber film, wherein disposing the absorber layer comprises depositing in one or more layers:
- a first material and a second material onto a window stack in a first deposition environment, wherein:
- the first material comprises a II-VI semiconductor or a II-VI semiconductor material precursor, and
- the second material comprises a group V dopant or a group V dopant precursor;
- applying a first heat treatment to the absorber film in a first heat-treating environment;
- contacting at least a portion of the absorber film with a passivating agent;
- applying a second heat treatment to the absorber film in a second heat-treating environment;
- and
- supplying a reducing gas to the second heat-treating environment to produce a reducing environment.
6 more elements
A photovoltaic semiconductor absorber layer comprising:
- an absorber film doped with a group V dopant, wherein the absorber film comprises a polycrystalline II-VI semiconductor, in a thickness of about 0.5 μm to 3.5 μm, and a group V dopant wherein:
- a concentration of the group V dopant in the absorber layer is between about 1×1016 cm−3 to about 5×1020 cm−3 throughout the thickness of the absorber layer, and
- 0.5 at. % to 10 at. % of the group V dopant is activated.
Dependencies are inferred from the claim text.