Donald J Sawdai

6784514, Aug 31, 2004

Oct 14, 2003

10/684910

Donald J. Sawdai - Redondo Beach CA
Augusto L. Gutierrez-Aitken - Redondo Beach CA

Northrop Grumman Corporation - Los Angeles CA

H01L 27095

257472, 257473, 257449

A preferred embodiment of the present invention provides a Schottky diode formed from a conductive anode contact, a semiconductor junction layer supporting the conductive contact and a base layer ring formed around at least a portion of the conductive anode contact. In particular, the base layer ring has material removed to form layer material gap (e. g. , a vacuum gap) adjacent to the conductive anode contact. A dielectric layer is also provided to form one boundary of the base layer material gap.

6924203, Aug 2, 2005

May 27, 2003

10/445612

Donald James Sawdai - Redondo Beach CA, US
Gregory Scott Leslie - Irvine CA, US
Augusto Gutierrez-Aitken - Redondo Beach CA, US

Northrop Grumman Corporation - Los Angeles CA

H01L021/332

438319, 438312, 438318, 438343, 438349, 438738, 438739

A heterojunction bipolar transistor (HBT) device structure is provided which facilitates the reduction of the base-collector capacitance and a method for making the same. The base-collector capacitance is decreased by fabricating a base micro-bridge connecting a base contact to a base mesa on the HBT. The base micro-bridge is oriented along about one of 001, 010, 00{overscore (1)}, and 0{overscore (1)}0 direction to a major flat of the wafer. The HBT device employs a phosphorous based collector material. During removal of the phosphorous based collector material, the base layer is undercut forming the micro-bridge, successfully removing the collector and sub-collector material below the bridge due to the orientation of the micro-bridge. The removal of collector and sub-collector material reduces the base-collector junction area, and therefore reduce the base-collector junction capacitance.

7038256, May 2, 2006

Dec 3, 2004

11/003575

Donald J. Sawdai - Redondo Beach CA, US
Augusto L. Gutierrez-Aitken - Redondo Beach CA, US

Northrop Grumman Corp. - Los Angeles CA

H01L 31/0328

257197, 257198

A double heterojunction bipolar transistor structure having desirable properties of a low base-emitter turn-on voltage and no electron blocking discontinuities in the base-collector junction. These properties are achieved by selecting base, emitter and collector materials to provide a bandgap profile that exhibits abrupt transitions at the heterojunctions, such that both abrupt transitions are due to transitions in the valence band edge of the bandgap, but not in the conductive band edge of the bandgap.

7084040, Aug 1, 2006

Apr 23, 2004

10/830729

Vincent Gambin - Torrance CA, US
Donald J. Sawdai - Redondo Beach CA, US

Northrop Grumman Corp. - Los Angeles CA

H01L 21/331

438312, 438343

Formation of a regrowth layer of a Group III–V semiconductor material is facilitated by prior formation of an intermediate layer, selected primarily for its smooth morphology properties. The intermediate layer is formed over an underlying substrate and over a dielectric layer formed over portions of the substrate. The intermediate layer maintains the monocrystalline properties of the underlying substrate in regions other than those covered by the dielectric layer, and improves the electrical and morphology properties of the regrowth layer formed over the intermediate layer.

8334550, Dec 18, 2012

Jun 9, 2011

13/156525

Donald J. Sawdai - Redondo Beach CA, US
Kwok K. Loi - Cerritos CA, US
Vesna Radisic - Manhattan Beach CA, US

Northrop Grumman Systems Corporation - Falls Church VA

H01L 29/66

257104, 257 9, 257471, 257607, 257E29332, 438979

A unipolar diode with low turn-on voltage includes a subcathode semiconductor layer, a low-doped, wide bandgap cathode semiconductor layer, and a high-doped, narrow bandgap anode semiconductor layer. A junction between the cathode layer and the anode layer creates an electron barrier in the conduction band, with the barrier configured to produce a low turn-on voltage for the diode. A unipolar diode with low turn-on voltage includes an n subcathode semiconductor layer, a low-doped, wide bandgap cathode semiconductor layer, and an n narrow bandgap anode semiconductor layer. Again, a junction between the cathode layer and the anode layer creates an electron barrier in the conduction band, with the barrier configured to produce a low turn-on voltage for the diode.

20050184312, Aug 25, 2005

Apr 28, 2005

11/116745

Donald Sawdai - Redondo Beach CA, US
Gregory Leslie - Irvine CA, US
Augusto Gutierrez-Aitken - Redondo Beach CA, US

H01L029/739

257197000

A heterojunction bipolar transistor (HBT) device structure is provided which facilitates the reduction of the base-collector capacitance and a method for making the same. The base-collector capacitance is decreased by fabricating a base micro-bridge connecting a base contact to a base mesa on the HBT. The base micro-bridge is oriented along about one of 001, 010, 00{overscore (1)}, and 0{overscore (1)}0 direction to a major flat of the wafer. The HBT device employs a phosphorous based collector material. During removal of the phosphorous based collector material, the base layer is undercut forming the micro-bridge, successfully removing the collector and sub-collector material below the bridge due to the orientation of the micro-bridge. The removal of collector and sub-collector material reduces the base-collector junction area, and therefore reduce the base-collector junction capacitance.

6653707, Nov 25, 2003

Sep 8, 2000

09/658222

Donald J. Sawdai - Redondo Beach CA
Augusto L. Gutierrez-Aitken - Redondo Beach CA

Northrop Grumman Corporation - Redondo Beach CA

H01L 27095

257472, 257473, 257481, 257483, 257485

A preferred embodiment of the present invention provides a Schottky diode ( ) formed from a conductive anode contact ( ), a semiconductor junction layer ( ) supporting the conductive contact ( ) and a base layer ring ( ) formed around at least a portion of the conductive anode contact ( ). In particular, the base layer ring ( ) has material removed to form a base layer material gap ( ) (e. g. , a vacuum gap) adjacent to the conductive anode contact ( ). A dielectric layer ( ) is also provided to form one boundary of the base layer material gap ( ).