Spectrolab, Inc.

Hughes Aircraft Company

Hughes Electronics Corporation

The Boeing Company

David R Lillington

Hans G Dill

George F Garlick

Gregory S Glenn

Jerry R Kukulka

Joseph A Minahan

David E Joslin

Nick Mardesich

Stephen C Miller

Kou-I Chang

A solar cell structure includes a solar cell having a front side and a back side and an active semiconductor structure. The solar cell produces a voltage when the front side is illuminated. The solar cell is protected by a by-pass diode structure including a by-pass diode positioned at the back side of the solar cell. A first electrical interconnection structure extends between the back side of the solar cell and the first diode terminal, and a second electrical interconnection structure extends between the front side of the solar cell and the second diode terminal. An entire length of the second electrical interconnection structure contacts the solar cell.

Solar cell structure with by-pass diode and wrapped front-side diode interconnection

A photovoltaic device uses a spectrally selective photon partitioner such as a reflector to partition incoming sunlight which is directed towards different solar cells, depending upon its energy. Solar cells having low and high energy band gaps are used, in which low energy photons are imaged towards that cell having the lower energy band gap, whereas high energy photons are imaged towards the higher energy band gap cell. By more directly imaging photons towards those cells in which they are converted to electricity, absorption losses due to free carriers in the semiconductor layers are reduced. The spectrally selective photon partitioner allows semiconductor layers having different lattice spacings to be optically coupled.

High efficiency tandem solar cells, and operating method

A two-terminal voltage or current matched solar cell has up to four photovoltaically active junctions which efficiently convert solar radiation into electricity. The solar cell comprises GaInP, GaAs, and GaInAsP, and in the four junction case, GaInAs is used as well. The invention allows the solar spectrum to be converted into electricity more efficiently than previously.

High efficiency multi-junction solar cells

A monolithically integrated solar cell microarray includes an isolation layer or multiple isolation layers between a substrate and a solar cell layer, and a trench in the solar cell layer that exposes the isolation layer. Together the isolation layer and trench define solar cells that are spaced apart and electrically isolated on the monolithic substrate. The solar cells are scaled to provide a desired current. Base contacts and integral emitter contact/interconnects connect a number of the scaled solar cells in series to sum their voltages to supply a desired output voltage and current. The trench and integral emitter contact/interconnects are formed using photolithographic etching and liftoff processes, respectively, which are much quicker and less expensive than the conventional dicing and soldering processes.

Monolithically integrated solar cell microarray and fabrication method

A photoresponsive layer formed of a semiconductive material such as gallium arsenide has differently doped strata which define a junction therebetween, and generates a photovoltaic effect in response to light incident on a front surface thereof. A front electrode is formed on the front surface. A structurally supporting back electrode open conductive support or grid structure is formed on a back surface of the photoresponsive layer. The support structure is sufficiently thick, approximately 12 to 125 microns, to prevent breakage of the photoresponsive layer, which may be as thin as approximately 25 to 100 microns. The support structure has a pattern selected to prevent propagation of a crack through the photoresponsive layer thereof.

Photovoltaic cell having structurally supporting open conductive back

A solar cell is disclosed wherein both the emitter and the base electrical contacts for a solar cell are disposed on the back major surface. Holes extend through the back major surface and the base layer to the emitter layer. The walls of the holes are doped to the same conductivity as the front emitter layer. Emitter contacts are deposited on the back major surface of the cell and extend into the holes making electrical contact to the emitter layer for collecting light generated current carriers. The base contacts are also disposed on the back major surface, and antireflection coatings are deposited on the emitter front major layer. Consequently, the front of the solar cell can be made smooth and therefore, a specularly reflective (non-scattering) solar cell results.

Controlled reflectance solar cell

Apparatus is disclosed for protecting delicate sensor optics from the damaging effects of unwanted powerful laser radiation. A thin-film reflective pellicle 14 is placed in the light path of a sensor telescope. Incident light 10 is focused by some combination of optical elements 12 onto the reflective surface 28 of the laser hazard protector 14. The reflected light 10 is then imaged by further optics 16 onto a detector array 18. Should a signal too strong for the detector enter the sensor aperture with the incident light 10, the focused power at the surface of the pellicle 28 will ablate the carbon and metallic film, burning a hole in the pellicle, and the high-power light 11 will be deflected from the detector array and be absorbed instead by the beam dump 20. A power meter within the beam dump determines when the laser threat has stopped and signals the turning mechanisms 15a and 15b to turn the pellicle reflector to a fresh position at which point normal sensor operations may resume. The reflective film for the laser hazard protector has a carbon supporting film placed after the reflective coating. The reflective coating has a uniform broadband absorption to laser light and can protect a sensor from a variety of potential threats. The present invention provides a sensor protection system with an extremely short response time, widband protection, and an unmatched margin of safety.

Apparatus for diverting electromagnetic radiation from sensitive optical

A gallium arsenide solar cell is disclosed having an aluminum gallium arsenide window layer in which fine metallic contact lines extend through the aluminum gallium arsenide window to electrically contact the emitter layer, and a plurality of metallic grid lines disposed on the window layer cross the contact lines, thereby making electrical contact to the metallic contact lines. A flat metallic strip extending along one of the edges of the solar cell electrically couples the grid lines to one another. Consequently, two separate metals can be used, one with good ohmic contact properties for the grid lines and another with good adhesion and current conducting properties for the current collecting bars. Additionally, the metallic contacts lines can be made very narrow to reduce the contact area to the emitter thereby reducing the recombination current in the emitter.

Growing community of inventors

Rancho Palos Verdes, CA, United States of America

David R Lillington