Ruth A Garcia

US Patent:

6632730, Oct 14, 2003

Filed:

Mar 29, 2000

Appl. No.:

09/538034

Inventors:

Daniel L. Meier - Pittsburgh PA
Hubert P. Davis - Pittsburgh PA
Ruth A. Garcia - Irwin PA
Joyce A. Jessup - McKeesport PA

Assignee:

Ebara Solar, Inc. - Belle Vernon PA

International Classification:

H01L 2126

US Classification:

438538, 438530, 438533, 438557, 438607, 438659

Abstract:

The present invention provides a system and method for creating self-doping contacts to silicon devices in which the contact metal is coated with a layer of dopant and subjected to high temperature, thereby alloying the silver with the silicon and simultaneously doping the silicon substrate and forming a low-resistance ohmic contact to it. A self-doping negative contact may be formed from unalloyed silver which may be applied to the silicon substrate by either sputtering, screen printing a paste or evaporation. The silver is coated with a layer of dopant. Once applied, the silver, substrate and dopant are heated to a temperature above the AgâSi eutectic temperature (but below the melting point of silicon). The silver liquefies more than a eutectic proportion of the silicon substrate. The temperature is then decreased towards the eutectic temperature.

US Patent:

6664631, Dec 16, 2003

Filed:

Jun 20, 2002

Appl. No.:

10/177880

Inventors:

Daniel L. Meier - Pittsburgh PA
Hubert P. Davis - Pittsburgh PA
Ruth A. Garcia - Irwin PA
Joyce A. Jessup - McKeesport PA

Assignee:

Ebara Solar, Inc. - Belle Vernon PA

International Classification:

H01L 2348

US Classification:

257743, 257748

Abstract:

The present invention provides a system for self-doping contacts to silicon devices in which the contact metal is coated with a layer of dopant and subjected to high temperature, thereby alloying the silver with the silicon and simultaneously doping the silicon substrate and forming a low-resistance ohmic contact to it. The silver is coated with a layer of dopant. Once applied, the silver, substrate and dopant are heated to a temperature above the AgâSi eutectic temperature (but below the melting point of silicon). The silver liquefies more than a eutectic proportion of the silicon substrate. This alloy of silver and silicon is the final contact material, and is composed of eutectic proportions of silicon and silver. Under eutectic proportions there is significantly more silver than silicon in the final contact material, thereby insuring good electrical conductivity of the final contact material.

US Patent:

6703295, Mar 9, 2004

Filed:

Apr 1, 2003

Appl. No.:

10/405298

Inventors:

Daniel L. Meier - Pittsburgh PA
Hubert P. Davis - Pittsburgh PA
Ruth A. Garcia - Irwin PA
Joyce A. Jessup - McKeesport PA

Assignee:

Ebara Corporation - Tokyo

International Classification:

H01L 2124

US Classification:

438537, 438659, 438661, 438686

Abstract:

The present invention provides a system and method for creating self-doping contacts to silicon devices in which the contact metal is coated with a layer of dopant and subjected to high temperature, thereby alloying the silver with the silicon and simultaneously doping the silicon substrate and forming a low-resistance ohmic contact to it. A self-doping negative contact may be formed from unalloyed silver which may be applied to the silicon substrate by either sputtering, screen printing a paste or evaporation. The silver is coated with a layer of dopant. Once applied, the silver, substrate and dopant are heated to a temperature above the AgâSi eutectic temperature (but below the melting point of silicon). The silver liquefies more than a eutectic proportion of the silicon substrate. The temperature is then decreased towards the eutectic temperature.

US Patent:

6737340, May 18, 2004

Filed:

Jun 19, 2002

Appl. No.:

10/176451

Inventors:

Daniel L. Meier - Pittsburgh PA
Hubert P. Davis - Pittsburgh PA
Ruth A. Garcia - Irwin PA
Joyce A. Jessup - McKeesport PA

Assignee:

Ebara Corporation - Tokyo

International Classification:

H01L 21225

US Classification:

438557, 438530, 438533, 438538, 438607, 438659

Abstract:

The present invention provides a system and method for creating self-doping contacts to silicon devices in which the contact metal is coated with a layer of dopant and subjected to high temperature, thereby alloying the silver with the silicon and simultaneously doping the silicon substrate and forming a low-resistance ohmic contact to it. A self-doping negative contact may be formed from unalloyed silver which may be applied to the silicon substrate by either sputtering, screen printing a paste or evaporation. The silver is coated with a layer of dopant. Once applied, the silver, substrate and dopant are heated to a temperature above the AgâSi eutectic temperature (but below the melting point of silicon). The silver liquefies more than a eutectic proportion of the silicon substrate. The temperature is then decreased towards the eutectic temperature.

US Patent:

62623591, Jul 17, 2001

Filed:

Oct 7, 1999

Appl. No.:

9/414990

Inventors:

Daniel L. Meier - Pittsburgh PA
Hubert P. Davis - Pittsburgh PA
Ruth A. Garcia - Irwin PA
Jalal Salami - West Mifflin PA

Assignee:

Ebara Solar, Inc. - Large PA

International Classification:

H01L 31068
H01L 3104

US Classification:

136256

Abstract:

A process for fabricating a solar cell is described. The process includes: (1) providing a base layer, (2) fabricating an emitter layer of p-type conductivity on a same side as the non-illuminated surface of the base layer to provide a strongly doped p-type emitter layer and a p-n junction between the n-type base layer and the p-type emitter layer. The base layer of the present invention has n-type conductivity and is defined by an illuminated surface and a non-illuminated surface. The illuminated surface has light energy impinging thereon when the solar cell is exposed to the light energy and the non-illuminated surface is opposite the illuminated surface.