Robert W Hilton

US Patent:

49633341, Oct 16, 1990

Filed:

Aug 14, 1989

Appl. No.:

7/393169

Inventors:

Brian S. Ahern - Boxboro MA
Robert M. Hilton - Chelmsford MA

Assignee:

The United States of America as represented by the Secretary of the Air
Force - Washington DC

International Classification:

C30B 1522
C30B 1524

US Classification:

422249

Abstract:

A heat pipe coracle is provide for use in a crystal growth apparatus; the heat pipe coracle includes a coracle ring, the coracle ring being composed of a material resistant to attack from a melt of the crystal growth apparatus and having density less than the melt so as to float upon the melt, the coracle ring having a central opening therethrough, the central opening being of a diameter approximately equal to that of a single crystal pulled from the melt through said central opening, the single crystal being in sliding contact with the coracle ring to insure uniform heat distribution about a vertical axis near an interface between the single crystal and the melt, and means for centering the coracle ring within a crucible of the crystal growth apparatus, the means for centering fixedly attached to the coracle ring and resistant to attack from said melt, the means for centering being in sliding contact with the wall of the crucible so that the heat pipe coracle can float upon said melt and below an encapsulating fluid, as desired, and move in a vertical direction.

US Patent:

54939852, Feb 27, 1996

Filed:

Feb 26, 1993

Appl. No.:

8/025208

Inventors:

David Bliss - Arlington MA
Robert M. Hilton - Sandwich MA
Joseph A. Adamski - Framingham MA

Assignee:

The United States of America as represented by the Secretary of the Air
Force - Washington DC

International Classification:

C30B 1700

US Classification:

117 83

Abstract:

The present invention is a process and apparatus for the synthesis and growth of single crystals of phosphorus compounds starting with the elemental materials in a single furnace without external exposure. The apparatus of the present invention is a crystal growth furnace heated by RF coils. Inside the furnace is a susceptor for holding a crucible. Above the crucible is selectively positioned a phosphorus improved injector. The non-phosphorus materials are placed in the crucible and melted to a desired temperature. The phosphorus material previously placed within the injector is heated by the radiant heat from the crucible to drive the phosphorus vapor into the melt through a tube. This is closely controlled by noting the temperature within the injector and adjusting the height of the injector above the melt to control the temperature within the phosphorus material. After the formation of the stoichiometric melt, the seed is inserted into the melt for crystal growth if so desired.

US Patent:

52521753, Oct 12, 1993

Filed:

Jun 29, 1990

Appl. No.:

7/546063

Inventors:

Steven Bachowski - Woburn MA
Brian S. Ahern - Boxboro MA
Robert M. Hilton - Chelmsford MA
Joseph A. Adamski - Framingham MA

Assignee:

The United States of America as represented by the Secretary of the Air
Force - Washington DC

International Classification:

C30B 1102

US Classification:

1566202

Abstract:

In the liquid encapsulated Kyropoulos process, the crystal is allowed to grow to the limits of the crucible and remain under the encapsulant fluid. In order to relieve the melt pressure between the growing crystal and the crucible, at least one capillary pressure relief hole is placed in the crucible which allows some of the melt to leak therefrom to relieve pressure.