Sandra L Collins

US Patent:

54964164, Mar 5, 1996

Filed:

Aug 5, 1994

Appl. No.:

8/286673

Inventors:

Robert B. Hall - Newark DE
Allen M. Barnett - Newark DE
Sandra R. Collins - Chesapeake City MD
Joseph C. Checchi - Newark DE
David H. Ford - Wilmington DE
Christopher L. Kendall - Wilmington DE
Steven M. Lampo - Elkton MD
James A. Rand - Oxford PA

Assignee:

Astropower, Inc. - Newark DE

International Classification:

H10L 310392
H10L 310368
H10L 3118

US Classification:

136258

Abstract:

The invention relates to techniques for manufacturing columnar-grained polycrystalline sheets which have particular utility as substrates or wafers for solar cells. The sheet is made by applying granular silicon to a setter material which supports the granular material. The setter material and granular silicon are subjected to a thermal profile all of which promote columnar growth by melting the silicon from the top downwardly. The thermal profile sequentially creates a melt region at the top of the granular silicon and then a growth region where both liquid and a growing polycrystalline sheet layer coexist. An annealing region is created where the temperature of the grown polycrystalline silicon sheet layer is controllably reduced to effect stress relief.

US Patent:

RE361569, Mar 23, 1999

Filed:

Jan 24, 1997

Appl. No.:

8/788660

Inventors:

Robert B. Hall - Newark DE
Allen M. Barnett - Newark DE
Sandra R. Collins - Chesapeake City MD
Joseph C. Checchi - Newark DE
David H. Ford - Wilmington DE
Christopher L. Kendall - Wilmington DE
Steven M. Lampo - Elkton MD
James A. Rand - Oxford PA

Assignee:

Astropower, Inc. - Newark DE

International Classification:

H01L 310392
H01L 310368
H01L 3118

US Classification:

136258

Abstract:

The invention relates to techniques for manufacturing columnar-grained polycrystalline sheets which have particular utility as substrates or wafers for solar cells. The sheet is made by applying granular silicon to a setter material which supports the granular material. The setter material and granular silicon are subjected to a thermal profile all of which promote columnar growth by melting the silicon from the top downwardly. The thermal profile sequentially creates a melt region at the top of the granular silicon and then a growth region where both liquid and a growing polycrystalline sheet layer coexist. An annealing region is created where the temperature of the grown polycrystalline silicon sheet layer is controllably reduced to effect stress relief.

US Patent:

61111910, Aug 29, 2000

Filed:

Mar 2, 1998

Appl. No.:

9/033155

Inventors:

Robert B. Hall - Newark DE
Allen M. Barnett - Newark DE
Sandra R. Collins - Chesapeake City MD
Joseph C. Checchi - Newark DE
David H. Ford - Wilmington DE
Christopher L. Kendall - Hockessin DE
James A Rand - Landenberg PA
Chad B. Moore - Corning NY

Assignee:

AstroPower, Inc. - Newark DE

International Classification:

H01L 2500

US Classification:

136258PC

Abstract:

The invention relates to improved techniques for manufacturing columnar-grained polycrystalline sheets which have particular utility as substrates or wafers for solar cells. The sheet is made from silicon on a setter material which supports the silicon material. The setter material and silicon are subjected to a thermal profile all of which promote columnar growth. The thermal profile sequentially creates a melt region where a thin-film capping layer grows at the top of the silicon, a nucleation region where preferential nucleation occurs at the capping-layer/molten-silicon interface, and then a growth region where both liquid and a growing polycrystalline sheet layer coexist. An annealing region is created where the temperature of the grown polycrystalline silicon sheet layer is controllably reduced to effect stress relief.