Mei H Cheng

US Patent:

53042484, Apr 19, 1994

Filed:

Jan 22, 1992

Appl. No.:

7/823942

Inventors:

David Cheng - Sunnyvale CA
Mei Cheng - Cupertino CA

Assignee:

Applied Materials, Inc. - Santa Clara CA

International Classification:

H01L 2100

US Classification:

118728

Abstract:

An improved apparatus for CVD processing is described wherein a wafer mounted on a vertically movable susceptor beneath a gas outlet or showerhead is raised into contact with a shield ring which normally rests on a ring support in the chamber. The shield ring engages the frontside edge of the wafer, lifting the shield ring off its support, when the susceptor and the wafer 10 are raised to a deposition position in the chamber. The shield ring, by engaging the frontside edge of the wafer, shields the edge of the top surface of the wafer, as well as the end edge and the backside of the wafer, during the deposition. Matching tapered edges, respectively, on the susceptor and the shield ring permit alignment of the shield ring with respect to the susceptor, and alignment of the wafer to the susceptor and the shield ring. Alignment means are also disclosed to circularly align the shield ring to its support in the chamber. Multi-unit shield rings permit the use of wider shield rings and prevent cracking of the shield ring due to thermal stresses caused by temperature differences near and away from the wafer during processing.

US Patent:

46683380, May 26, 1987

Filed:

Dec 30, 1985

Appl. No.:

6/814638

Inventors:

Dan Maydan - Los Altos Hills CA
Sasson Somekh - Redwood City CA
Mei Cheng - San Jose CA
David Cheng - San Jose CA

Assignee:

Applied Materials, Inc. - Santa Clara CA

International Classification:

H01L 21306
B44C 122
C03C 1500
C03C 2506

US Classification:

156643

Abstract:

A magnetically-enhanced, variable magnetic field, RIE mode plasma etch process for etching materials such as dielectrics and polycrystalline, is disclosed. The variable magnetic field permits optimization of selected characteristics such as etch rate, etch selectivity, ion bombardment and radiation damage, etch uniformity, and etch anisotropy.

US Patent:

51124351, May 12, 1992

Filed:

Nov 29, 1989

Appl. No.:

7/443811

Inventors:

David N. Wang - Cupertino CA
Mei Cheng - San Jose CA
Toung K. Leong - late of Santa Clara CA

Assignee:

Applied Materials, Inc. - Santa Clara CA

International Classification:

H01L 2100

US Classification:

156643

Abstract:

Gas chemistry and a related RIE mode process is described for etching silicides of the refractory metals titanium, tantalum, tungsten and aluminum and for etching composites of these silicides on polycrystalline silicon layers. BCl. sub. 3 is added to the HCl/Cl. sub. 2 gas chemistry used for the polysilicon etch along with additives selected from fluorinated gases and oxygen to satisfy the multiple requirement of the two-step silicide-polysilicon etch process, including the silicide-to-polysilicon etch ratio requirement.