A detector for optical detection of at least one object, the detector including: at least one optical sensor including at least one sensor region. The optical sensor is configured to generate at least one sensor signal dependent on an illumination of the sensor region by an incident modulated light beam. The sensor signal is dependent on a modulation frequency of the light beam. The sensor region includes at least one capacitive device including at least two electrodes. At least one insulating layer and at least one photosensitive layer are embedded between the electrodes, wherein at least one of the electrodes is at least partially optically transparent for the light beam. The detector further includes at least one evaluation device configured to generate at least one item of information on a position of the object by evaluating the sensor signal.

A photovoltaic device includes a first contact and a hybrid absorber layer. The hybrid absorber layer includes a chalcogenide layer and a semiconductor layer in contact with the chalcogenide layer. A buffer layer is formed on the absorber layer, and a transparent conductive contact layer is formed on the buffer layer.

A method of fabricating a photovoltaic device includes performing fabrication operations to form the photovoltaic device. The fabrication operations include replacing a portion of selenium with sulfur in a copper zinc tin sulfur selenium alloy (CZTSSe) material arranged on a substrate to form a sulfur enriched CZTSSe material to alter a band gap of the CZTSSe material. The fabrication operations include removing surface secondary phases or degraded portions of the sulfur enriched CZTSSe material to form a single phase sulfur enriched CZTSSe material. The fabrication operations further include replacing the substrate in contact with the single phase sulfur enriched CZTSSe material with a different contact material to form an exfoliated sulfur enriched CZTSSe device.

An integrated kesterite (e.g., CZT(S,Se)) photovoltaic device and battery is provided. In one aspect, a method of forming an integrated photovoltaic device and battery includes: forming a photovoltaic device having a substrate, an electrically conductive layer, an absorber layer, a buffer layer, a transparent front contact, and a metal grid; removing the substrate and the electrically conductive layer from the photovoltaic device to expose a backside surface of the absorber layer; forming at least one back contact on the backside surface of the absorber layer; and integrating the photovoltaic device with a battery, wherein the integrating includes connecting i) a positive contact of the battery with the back contact on the backside surface of the absorber layer and ii) a negative contact of the battery with the metal grid on the transparent front contact. An integrated photovoltaic device and battery is also provided.

Techniques for forming an ohmic back contact for Ag.sub.2ZnSn(S,Se).sub.4 photovoltaic devices. In one aspect, a method for forming a photovoltaic device includes the steps of: depositing a refractory electrode material onto a substrate; depositing a contact material onto the refractory electrode material, wherein the contact material includes a transition metal oxide; forming an absorber layer on the contact material, wherein the absorber layer includes Ag, Zn, Sn, and at least one of S and Se; annealing the absorber layer; forming a buffer layer on the absorber layer; and forming a top electrode on the buffer layer. The refractory electrode material may be Mo, W, Pt, Ti, TiN, FTO, and combinations thereof. The transition metal oxide may be TiO.sub.2, ZnO, SnO, ZnSnO, Ga.sub.2O.sub.3, and combinations thereof. A photovoltaic device is also provided.

A method for fabricating a photovoltaic device includes forming a two dimensional material on a first monocrystalline substrate. A single crystal absorber layer including CuZnSnS(Se) (CZTSSe) is grown over the first monocrystalline substrate. The single crystal absorber layer is exfoliated from the two dimensional material. The single crystal absorber layer is transferred to a second substrate, and the single crystal absorber layer is placed on a conductive layer formed on the second substrate. Additional layers are formed on the single crystal absorber layer to complete the photovoltaic device.

Techniques for forming an ohmic back contact for Ag.sub.2ZnSn(S,Se).sub.4 photovoltaic devices. In one aspect, a method for forming a photovoltaic device includes the steps of: depositing a refractory electrode material onto a substrate; depositing a contact material onto the refractory electrode material, wherein the contact material includes a transition metal oxide; forming an absorber layer on the contact material, wherein the absorber layer includes Ag, Zn, Sn, and at least one of S and Se; annealing the absorber layer; forming a buffer layer on the absorber layer; and forming a top electrode on the buffer layer. The refractory electrode material may be Mo, W, Pt, Ti, TiN, FTO, and combinations thereof. The transition metal oxide may be TiO.sub.2, ZnO, SnO, ZnSnO, Ga.sub.2O.sub.3, and combinations thereof. A photovoltaic device is also provided.

Photovoltaic structures having multiple absorber layers separated by a diffusion barrier are provided. In one aspect, a method of forming an absorber on a substrate includes: depositing a first layer of light absorbing material on the substrate; depositing a diffusion barrier; depositing a second layer of light absorbing material on the diffusion barrier, wherein the first layer of light absorbing material has a different band gap from the second layer of light absorbing material; and annealing the absorber, wherein the diffusion barrier prevents diffusion of elements between the first layer of light absorbing material and the second layer of light absorbing material during the annealing. A solar cell and method for formation thereof are also provided.

Methods of fabricating photovoltaic cells are provided. The photovoltaic cells include a transparent substrate to allow light to enter the photovoltaic cell through the substrate, and a light absorption layer associated with the substrate. The light absorption layer has opposite first and second surfaces, with the first surface being closer to the transparent substrate than the second surface. A passivation layer is disposed over the second surface of the light absorption layer, and a plurality of first discrete contacts and a plurality of second discrete contacts are provided within the passivation layer to facilitate electrical coupling to the light absorption layer. A first electrode and a second electrode are disposed over the passivation layer to contact the plurality of first discrete contacts and the plurality of second discrete contacts, respectively. The first and second electrodes may include a photon-reflective material.

The invention relates to an optical detector (110) for an optical detection, in particular, of radiation within the infrared spectral range, specifically, with regard to sensing at least one optically conceivable property of an object (112). More particular, the optical detector (110) may be used for determining transmissivity, absorption, emission, reflectance, and/or a position of at least one object (112). Further, the invention relates to a method for manufacturing the optical detector (110) and to various uses of the optical detector (110). The optical detector (110) comprises an optical filter (114) having at least a first surface (116) and a second surface (118), the second surface (118) being located oppositely with respect to the first surface (116), wherein the optical filter (114) is designed for allowing an incident light beam (120) received by the first surface (116) to pass through the optical filter (114) to the second surface (118), thereby generating a modified light beam (122) by modifying a spectral composition of the incident light beam (120); a sensor layer (128) comprising a photosensitive material (130) being deposited on the second surface (118) of the optical filter (114), wherein the sensor layer (128) is designed to generate at least one sensor signal in a manner dependent on an illumination of the sensor layer (128) by the modified light beam (122); and an evaluation device (140) designed to generate at least one item of information provided by the incident light beam (120) by evaluating the sensor signal. The optical detector (110) constitutes an improved simple, cost-efficient and, still, reliable detector for detecting optical radiation, especially within the infrared spectral range, specifically with regard to sensing at least one of transmissivity, absorption, emission and reflectance. Hereby, the optical detector (110) is capable of effectively removing stray light as far as possible.