Photovoltaic devices and method of manufacturing
AssigneeFirst Solar, Inc.
InventorsChangming Jin, Sanghyun Lee, Jun-Ying Zhang
Life of this patent
Estimating the term…
Abstract
Disclosed are methods for the surface cleaning and passivation of PV absorbers, such as CdTe substrates usable in solar cells, and devices made by such methods. In some embodiments, the method involves an anode layer ion source (ALIS) plasma discharge process to clean and oxidize a CdTe surface to produce a thin oxide layer between the CdTe layer and subsequent back contact layer(s).
Claims20
A photovoltaic device having a front contact stack including a front contact layer, a semiconductor stack disposed on the front contact stack, and a back contact stack disposed on the semiconductor stack, wherein the semiconductor stack comprises cadmium, tellurium, and at least one of:
- sulfur, selenium, zinc, or oxygen;
- the photovoltaic device further comprising:
- an oxide layer formed on the semiconductor stack between the semiconductor stack and the back contact stack, the oxide layer being from about 5 Å to about 50 Å thick.
A photovoltaic device having a front contact stack including a front contact layer, a semiconductor stack disposed on the front contact stack, and a back contact stack disposed on the semiconductor stack, wherein the back contact stack comprises a bilayer of a metal layer and a second layer comprising zinc and tellurium;
- the photovoltaic device further comprising:
- an oxide layer formed on the semiconductor stack between the semiconductor stack and the back contact stack, the oxide layer being from about 5 Å to about 50 Å thick.
A photovoltaic device comprising:
- a front contact stack comprising a transparent conductive oxide;
- a semiconductor stack disposed over the front contact stack, wherein the semiconductor stack comprises cadmium, tellurium, and at least one of:
- selenium, zinc, or oxygen;
- an oxide layer on the semiconductor stack, the oxide layer having a thickness from about 2 Å to about 100 Å;
- and
- a back contact stack over the oxide layer.
Dependencies are inferred from the claim text.