Texas Instruments Corporation

Other

Gary D Stevens

Gregory Barton Hotchkiss

Francois A Padovani

Jeffrey Scott Reynolds

Louanne Kay Brown

Harvey L Conklin

The invention discloses a method for attaching solder members ( ) to a substrate ( ). The method includes forming a decal ( ) with a plurality of solder members ( ). The method further comprises aligning the decal ( ) with the substrate ( ) and transferring the solder members ( ) on the decal ( ) to the substrate ( ).

Method and apparatus for attaching solder members to a substrate

A method (10) of phosphorus doping a semiconductor particle using ammonium phosphate. A p-doped silicon sphere is mixed with a diluted solution of ammonium phosphate having a predetermined concentration. These spheres are dried (16, 18), with the phosphorus then being diffused (20) into the sphere to create either a shallow or deep p-n junction. A good PSG glass layer is formed on the surface of the sphere during the diffusion process. A subsequent segregation anneal process is utilized to strip metal impurities from near the p-n junction into the glass layer. A subsequent HF strip procedure is then utilized to removed the PSG layer. Ammonium phosphate is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirement.

Phosphorous doping a semiconductor particle

The invention discloses a method for forming solder (114) on a substrate (112). The method includes forming a decal (110) with a plurality of solder regions (113). The method further comprises aligning the decal (110) with the substrate (112) and transferring the solder regions (113) on the decal (110) to the substrate (112).

Method and apparatus for forming solder on a substrate

A method (10,30) of boron doping a semiconductor particle using boric acid to obtain a p-type doped particle. Either silicon spheres or silicon powder is mixed with a diluted solution of boric acid having a predetermined concentration. The spheres are dried (16), with the boron film then being driven (18) into the sphere. A melt procedure mixes the driven boron uniformly throughout the sphere. In the case of silicon powder, the powder is metered out (38) into piles and melted/fused (40) with an optical furnace. Both processes obtain a p-type doped silicon sphere with desired resistivity. Boric acid is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirements.

Boron doping a semiconductor particle

A method and apparatus for forming semiconductor particles (42) for solar cells using an optical furnace (30). Uniform mass piles (26) of powered semiconductor feedstock are almost instantaneously optically fused to define high purity semiconductor particles without oxidation. The high intensity optical energy is directed and focused to the semiconductor feedstock piles (26) advanced by a conveyer medium (16) thereunder. The semiconductor feedstock piles (26) are at least partially melted and fused to form a single semiconductor particle (42) which can be later separated from a refractory layer (18) by a separator (50), preferably comprised of silica. The apparatus (10) and process is automated, providing a high throughput to produce uniform mass, high quality spheres for realizing high efficiency solar cells. The apparatus is energy efficient, whereby process parameters can be easily and quickly established.

Apparatus for making optically fused semiconductor powder for solar cells

Method of making optically fused semiconductor powder for solar cells

This invention is directed to a tie-down device for use with small trucks such as pickup trucks having sides. The sides comprise an exterior wall and an interior wall. There is positioned between the exterior wall and the interior wall an elongated member such as a rod or a tube. There is positioned on the elongated member a clamp having an eye bolt. A cargo box or cargo may be positioned on the bed of the pickup truck. A stretchable elastic tie-down device having a hook on each end may be stretched over the cargo box and attached to the eye bolt on one side of the pickup truck and to an eye bolt on the other side of the pickup truck to hold the cargo box in position.

Hidden adjustable tie-down device

A method of manufacturing semiconductor particles (30) of uniform mass. A template (12) is used to meter out uniform mass piles (28) of semiconductor feedstock upon a refractory layer (14). These piles (28) of semiconductor feedstock are then melted briefly to obtain semiconductor particles (30) of uniform mass. Silica is the preferred refractory layer, and is separated from the particles after the melt procedure. Subsequent melt procedures can be implemented to ultimately obtain perfect spheres of the semiconductor material. The present invention is well suited for forming semiconductor spheres to be implemented in photovoltaic solar cells. Semiconductor grade or metallurgical grade feedstock can be implemented to obtain particles of high purity. High yields of uniformly massed spheres can be obtained to produce high efficiency photovoltaic cells at a moderate cost.

Growing community of inventors

Dallas, TX, United States of America

Gary D Stevens