A photovoltaic device (100) can include an absorber layer (160). The absorber layer (160) can be doped p-type with a Group V dopant and can have a carrier concentration of the Group V dopant greater than 4×10.sup.15 cm.sup.−3. The absorber layer (160) can include oxygen in a central region of the absorber layer (160). The absorber layer (160) can include an alkali metal in the central region of the absorber layer (160). Methods for carrier activation can include exposing an absorber layer (160) to an annealing compound in a reducing environment (220). The annealing compound (224) can include cadmium chloride and an alkali metal chloride.

According to the embodiments provided herein, a photovoltaic device can include an absorber layer. The absorber layer can be doped p-type with a Group V dopant and can have a carrier concentration of the Group V dopant greater than 4×10.sup.15 cm.sup.−3. The absorber layer can include oxygen in a central region of the absorber layer. The absorber layer can include an alkali metal in the central region of the absorber layer. Methods for carrier activation can include exposing an absorber layer to an annealing compound in a reducing environment. The annealing compound can include cadmium chloride and an alkali metal chloride.

Photo-detection device (100) including a semiconductor substrate (110) made of Cd.sub.xHg.sub.1-xTe, with an N-doped region (120), a P-doped region (130), and a concentrated casing (150) only located in the P-doped region and having an average cadmium concentration greater than the average cadmium concentration in the N-doped region. According to the invention, the concentrated casing (150) has a cadmium concentration gradient, defining therein at least one intermediate gap zone (151) and at least one high gap zone (152), and the intermediate gap zone (151) is in direct physical contact with an electrical contact block (170). A significant reduction in the dark current and an optimal charge carrier collection are thus combined.

A photovoltaic cell can include an interfacial layer in contact with a semiconductor layer.

A photovoltaic device is disclosed including at least one Cadmium Sulfide Telluride (CdS.sub.xTe.sub.1−x) layer as are methods of forming such a photovoltaic device.

Described herein is a diffusion-based ex-situ group V element doping method in the CdCl.sub.2 heat-treated polycrystalline CdTe film. The ex-situ doping using group V halides, such as PCl.sub.3, AsCl.sub.3, SbCl.sub.3, or BiCl.sub.3, demonstrated a promising PCE of ˜18% and long-term light soaking stability in CdSe/CdTe and CdS/CdTe devices with decent carrier concentration>10.sup.15 cm.sup.−3. This ex-situ solution or vapor process can provide a low-cost alternative pathway for effective doping of As, as well as P, Sb, and Bi, in CdTe solar cells with limited deviation from the current CdTe manufacturing process.

The photoelectric conversion device includes a quantum dot accumulation zone, a base layer having current collecting properties which is disposed on at least one major surface of the quantum dot accumulation zone, and a plurality of columnar carrier collection zones, each extending from the base layer into the quantum dot accumulation zone and having an open end. Each of the carrier collection zones is composed mainly of metal oxide. An open end part has a higher mole ratio of oxygen to metal than a body part other than the open end part.

A layer of an n-type chalcogenide compositions provided on a substrate in the presence of an oxidizing gas in an amount sufficient to provide a resistivity to the layer that is less than the resistivity a layer deposited under identical conditions but in the substantial absence of oxygen.

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.

According to the embodiments provided herein, a method for doping an absorber layer can include contacting the absorber layer with an annealing compound. The annealing compound can include cadmium chloride and a group V salt comprising an anion and a cation. The anion, the cation, or both can include a group V element. The method can include annealing the absorber layer, whereby the absorber layer is doped with at least a portion of the group V element of the annealing compound.