Hughes Electronics Corporation

The Boeing Company

Spectrolab, Inc.

Hughes Aircraft Company

Gregory S Glenn

Michael L Rupp

David R Lillington

B Terence Cavicchi

William O Montjar

A solar cell structure has a solar cell unit structure including a heat sink, and a solar cell having a front side, a back side, and a solar-cell projected area coverage on the heat sink. The solar cell has an active semiconductor structure that produces a voltage between the front side and the back side when the front side is illuminated. An intermediate structure is disposed between and joined to the back side of the solar cell and to the heat sink. The intermediate structure has an intermediate-structure projected area coverage on the heat sink and includes a by-pass diode having a diode projected area coverage on the heat sink. The diode projected area coverage on the heat sink may be substantially the same as the intermediate-structure projected coverage on the heat sink. Alternatively, the diode projected area coverage on the heat sink maybe less than the solar-cell projected area coverage on the heat sink, and the intermediate structure further includes a substrate coplanar with the by-pass diode.

Solar cell structure with integrated discrete by-pass diode

A high solar flux photovoltaic concentrator receiver is disclosed for the generation of high electrical power at high efficiency for public and private use. The invention uses a wraparound interconnect to allow direct bonding of concentrator solar cells to a heat sink with solder or conductive epoxy. This approach allows series or parallel interconnection between multiple cells and provides for high thermal conductance to improve cooling the solar cells. Cooling the solar cells under high concentration of solar energy increases their electrical efficiency. A highly conductive di-electric is utilized to insulate the cell backs from the metal heat sink. The invention minimizes obscuration losses, improves thermal conduction, reduces coefficient of thermal expansion stresses, and can be produced at reduced manufacturing costs.

Low cost high solar flux photovoltaic concentrator receiver

An interconnect for connecting first and second solar cells comprises a base portion having a first distal section and a first intermediate section, with the first distal and intermediate sections being integral with the base portion and capable of fixture to the first solar cell. An extension tab is integral to the first distal section, with the extension tab being capable of fixture to a front side of the second solar cell. A diode tab is integral to the first intermediate section, with the diode tab being capable of fixture to a diode side of the second solar cell, such diode side being on a side opposite to the front side. Solar panels comprising solar cells interconnected with such interconnects are suitable for both terrestrial and non-terrestrial applications.

Solar panel and solar cell having in-plane solar cell interconnect with integrated diode tab

A solar cell module comprises a substrate and a first solar cell supported by the substrate, with the first solar cell having a first top side and a first rear side. A second solar cell is supported by the substrate and has a second top side and a second rear side, with the second solar cell being operatively adjacent the first solar cell. A first tab is affixed to either the first or second top side and operatively interfaces with a respective one of the first or second rear side. A bonding element is disposed between the substrate and first and second rear sides. The bonding element directly bonds (a) the substrate to one of the first and second rear sides and (b) the substrate to the tab. A first metal trace element is disposed between the substrate and first and second solar cells, with the metal trace electrically connecting one of the first and second top sides to one of the first and second rear sides with a conducting element.

Lightweight solar module and method of fabrication

An improved method of detecting and removing a shunt from a photoelectric semiconductor device comprises the steps of characterizing the device by generated data or performance graph; forward biasing the device; producing electromagnetic radiation from the device; receiving the radiation; associating a contrast in radiation to the defect; and mechanically removing the defect, whereby the defect is removed in the absence of a step of applying a chemical to the defect to assist in removing the defect.

Method for electrical shunt detection and removal on semiconductors

A welded wire termination for use in thermally and mechanically stressful environments is provided by forming a wire termination tab on a conductive pad to define a tubule for receiving a wire, either stranded or solid. The tubule is tweezer welded to form a welded termination joint between the wire and the conductive tab. The tubule easily captures all of the stranded wires and increases the surface area of the weld to a solid lead. A tweezer weld exerts pressure laterally on the tubule, and thus does not exert a force on the underlying substrate that could damage the substrate. This approach creates only a single electro-mechanical connection from the wire to the conductive pad, which is inherently more reliable than multiple connections such as those that are crimped first then welded.

Welded wire termination device and method

Welded wire termination device and method for constructing a solar array

A strap device clamps soldered wires to a conductive pad to reduce stress on the solder joints and to prevent the wire from springing off of the conductive pad if the solder joint should fail. This is accomplished by forming a conductive strap on a die into a yoke shape. The ends of the strap are then welded to a conductive pad so that the strap's yoke shape defines an opening between the strap and the conductive pad. A wire is inserted into the opening and soldered to form a solder joint between the wire, the strap, and the conductive pad. The strap reduces the stress on the solder joint by increasing its surface area and by clamping the wire to the conductive pad during the high temperature portion of a thermal cycle. If the solder joint should fail, the conductive strap maintains a electro-mechanical connection between the wire and the conductive pad.

Strap device clamping soldered wires for use in solar cell arrays

Thin semiconductor devices, such as thin solar cells, and a method of fabricating same are disclosed. A microblasting procedure is employed to thin a semiconductor wafer or substrate, such as a solar cell wafer, wherein fine abrasive particles are used to etch away wafer material through a mask. Thick areas remain at the perimeter of the semiconductor device or solar cell, in regions of the semiconductor device or solar cell behind the front interconnect attachment pads, and at corresponding rear interconnect attachment areas. In addition, there are thick areas in a pattern that comprise interconnected beams that support the thin wafer areas. Consequently, predetermined areas of the wafer are thinned to form a predetermined structural pattern in the wafer that includes an external frame and a plurality of interconnected beams. The final configuration of the semiconductor device or solar cell has approximately 20% of the area at the original wafer thickness with the remaining 80% etched away to a relatively thin thickness.

Method of fabrication of thin semiconductor device

A pattern of current collection gridlines (24) is formed on a surface (20) of a photovoltaic wafer (12). An ohmic contact strip (28) is formed adjacent to an edge (12c) of the wafer (12) in electrical interconnection with the gridlines (24). Interconnect tabs (30) are integrally formed with the gridlines (24) and contact strip (28), extending away from the contact strip (28) external of the edge (12c) for series or parallel interconnection with other solar cells. The interconnect tabs (30) may have a stress reflief configuration, including a non-planar bend or loop. The wafer (12) initially has a first portion (12a) and a second portion (12b). A barrier layer (50) of photoresist or the like is formed on the second portion (12b). The grid (24) and contact strip (28) are formed on the first portion (12a) simultaneously with forming the interconnect tabs (30) over the barrier layer (50 ) on the second portion (12b) using photolithography and metal deposition. The barrier layer (50) is dissolved away, and the second portion (12b) is broken away from the first portion (12a), leaving the interconnect tabs (30) extending from the contact strip (28) external of the remaining first portion (12a) of the wafer (12).

Method of fabricating solar cell with integrated interconnect

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 control system for parallel gap welders typically employed to weld contacts to solar cells or wires to integrated circuit chips is disclosed. The system monitors the temperature generated by the welder at the work pieces. The system automatically terminates the weld operation should the weld temperature reach a maximum predetermined temperature, thereby preventing overheating the weld joint and adjacent parts. Alternatively, if the weld temperature does not reach a minimum predetermined temperature the system automatically signals the weld operator that the joint must be rewelded to avoid an incomplete or cold weld. A quality weld can therefore be repeated.

Growing community of inventors

Pacific Palisades, CA, United States of America

Gregory S Glenn