Textured multi-junction solar cell and fabrication method
AssigneeInternational Business Machines Corporation
InventorsBAHMAN HEKMATSHOARTABARI, ALI KHAKIFIROOZ, GHAVAM G. SHAHIDI, DAVOOD SHAHRJERDI
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Abstract
A method for forming a multi-junction photovoltaic device includes providing a germanium layer and etching pyramidal shapes in the germanium layer such that (111) facets are exposed to form a textured surface. A first p-n junction is formed on or over the textured surface from III-V semiconductor materials. Another p-n junction is formed over the first p-n junction from III-V semiconductor materials and follows the textured surface.
Claims20
A multi-junction photovoltaic device, comprising:
- a germanium layer having pyramidal shapes with (111) facets exposed to form a textured surface;
- a first p-n junction formed on or over the textured surface;
- and
- at least one other p-n junction formed over the first p-n junction and following the textured surface.
A multi-junction photovoltaic device, comprising:
- a germanium layer having pyramidal shapes with (111) facets exposed to form a textured surface;
- and
- a plurality of p-n junctions formed from III-V semiconductor materials, the plurality of p-n junctions being formed to follow a shape of the (111) facets of the textured surface to increase light trapping and to increase overall device efficiency, the semiconductor III-V materials having an associated bandgap energy such that the p-n junctions are ordered by decreasing bandgap energies.
A multi-junction photovoltaic device, comprising:
- a germanium layer having pyramidal shapes with (111) facets exposed to form a textured surface;
- a first p-n junction formed on or in the germanium layer by doping a top portion of the germanium layer;
- a second p-n junction formed on the first p-n junction by an epitaxially grown GaAs-containing layer;
- a third p-n junction formed on the second p-n junction by an epitaxially grown GaP-containing layer;
- wherein the p-n junctions follow a shape of the (111) facets of the textured surface to increase light trapping and to increase overall device efficiency.
Dependencies are inferred from the claim text.