Christine Fisher Richardson

US Patent:

20110155045, Jun 30, 2011

Filed:

Jan 27, 2011

Appl. No.:

13/015258

Inventors:

Kaitlin Olsen - Arlington MA, US
Weidong Huang - Bolton MA, US
Christine Richardson - Northborough MA, US

Assignee:

EVERGREEN SOLAR, INC. - Marlborough MA

International Classification:

C30B 15/20
C30B 15/10

US Classification:

117 24, 117211, 425270

Abstract:

A sheet wafer growth system includes a crucible for containing molten material and an afterheater positioned above the crucible. The afterheater has an inner surface disposed toward the crucible. The system further includes one or more shields adjacent to the inner surface of the afterheater. The afterheater and the shield(s) are configured to allow a sheet wafer to pass adjacent to the shield(s). Each shield has two or more substantially different thermally conductive regions such that the two or more regions are configured to control the temperature profile of the growing sheet wafer.

US Patent:

20120125254, May 24, 2012

Filed:

Nov 23, 2010

Appl. No.:

12/952288

Inventors:

Brian D. Kernan - Newton MA, US
Gary J. Tarnowski - Acton MA, US
Weidong Huang - Bolton MA, US
Scott Reitsma - Shrewsbury MA, US
Christine Richardson - Northborough MA, US

Assignee:

EVERGREEN SOLAR, INC. - Marlborough MA

International Classification:

C30B 11/02

US Classification:

117 78

Abstract:

A method for reducing the range in resistivities of semiconductor crystalline sheets produced in a multi-lane growth furnace. A furnace for growing crystalline sheets is provided that includes a crucible with a material introduction region and a crystal growth region including a plurality of crystal sheet growth lanes. The crucible is configured to produce a generally one directional flow of material from the material introduction region toward the crystal sheet growth lane farthest from the material introduction region. Silicon doped with both a p-type dopant and an n-type dopant in greater than trace amounts is introduced into the material introduction region. The doped silicon forms a molten substance in the crucible called a melt. Crystalline sheets are formed from the melt at each growth lane in the crystal growth region. Co-doping the silicon feedstock can reduce the variation in resistivities among the crystalline sheets formed in each lane.