Kin Fung Yu

US Patent:

6759312, Jul 6, 2004

Filed:

Oct 16, 2002

Appl. No.:

10/272280

Inventors:

Wladyslaw Walukiewicz - Kensington CA
Kin M. Yu - Lafayette CA

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01L 21322

US Classification:

438473, 438167, 438520, 438407, 438515, 438 37, 438 46, 438379, 438606, 148171, 148175, 148187, 357 17, 357 63, 357 89, 357 90

Abstract:

Non-alloyed, low resistivity contacts for semiconductors using Group III-V and Group II-VI compounds and methods of making are disclosed. Co-implantation techniques are disclosed.

US Patent:

7217882, May 15, 2007

Filed:

May 27, 2003

Appl. No.:

10/445711

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US
Junqiao Wu - Richmond CA, US
William J. Schaff - Ithaca NY, US

Assignee:

Cornell Research Foundation, Inc. - Ithaca NY
The Regents of the University of California - Oakland CA

International Classification:

H01L 31/00

US Classification:

136252, 136262

Abstract:

An alloy having a large band gap range is used in a multijunction solar cell to enhance utilization of the solar energy spectrum. In one embodiment, the alloy is InGaN having an energy bandgap range of approximately 0. 7 eV to 3. 4 eV, providing a good match to the solar energy spectrum. Multiple junctions having different bandgaps are stacked to form a solar cell. Each junction may have different bandgaps (realized by varying the alloy composition), and therefore be responsive to different parts of the spectrum. The junctions are stacked in such a manner that some bands of light pass through upper junctions to lower junctions that are responsive to such bands.

US Patent:

7709728, May 4, 2010

Filed:

Nov 29, 2004

Appl. No.:

10/999456

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US
Junqiao Wu - Belmont MA, US

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01L 25/00
H01L 31/00

US Classification:

136243, 136252, 136258

Abstract:

The highly mismatched alloy ZnMnOTe, 0≦y

US Patent:

8039740, Oct 18, 2011

Filed:

Jul 13, 2007

Appl. No.:

11/777963

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US

Assignee:

RoseStreet Labs Energy, Inc. - Phoenix AZ

International Classification:

H01L 31/042

US Classification:

136261, 136262

Abstract:

A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

US Patent:

8129614, Mar 6, 2012

Filed:

Oct 17, 2011

Appl. No.:

13/275079

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US

Assignee:

RoseStreet Labs Energy - Phoenix AZ

International Classification:

H01L 31/042

US Classification:

136261, 136262

Abstract:

A single P-N junction solar cell is provided having two depletion regions for charge separation while allowing the electrons and holes to recombine such that the voltages associated with both depletion regions of the solar cell will add together. The single p-n junction solar cell includes an alloy of either InGaN or InAlN formed on one side of the P-N junction with Si formed on the other side in order to produce characteristics of a two junction (2J) tandem solar cell through only a single P-N junction. A single P-N junction solar cell having tandem solar cell characteristics will achieve power conversion efficiencies exceeding 30%.

US Patent:

8129615, Mar 6, 2012

Filed:

Jan 18, 2008

Appl. No.:

12/009505

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US
Junqiao Wu - Belmont MA, US

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01L 31/0264

US Classification:

136262, 136252, 257E31016, 257E31022, 257E31018, 438930, 438 93

Abstract:

The highly mismatched alloy ZnMnOTe, 0≦y

US Patent:

8232470, Jul 31, 2012

Filed:

Sep 11, 2009

Appl. No.:

12/558446

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US

Assignee:

Rosestreet Labs Energy, Inc. - Phoenix AZ

International Classification:

H01L 31/00

US Classification:

136262, 136252

Abstract:

An intermediate band solar cell (IBSC) is provided including a p-n junction based on dilute III-V nitride materials and a pair of contact blocking layers positioned on opposite surfaces of the p-n junction for electrically isolating the intermediate band of the p-n junction by blocking the charge transport in the intermediate band without affecting the electron and hole collection efficiency of the p-n junction, thereby increasing open circuit voltage (V) of the IBSC and increasing the photocurrent by utilizing the intermediate band to absorb photons with energy below the band gap of the absorber layers of the IBSC. Hence, the overall power conversion efficiency of a IBSC will be much higher than an conventional single junction solar cell. The p-n junction absorber layers of the IBSC may further have compositionally graded nitrogen concentrations to provide an electric field for more efficient charge collection.

US Patent:

20090173373, Jul 9, 2009

Filed:

Jan 2, 2009

Appl. No.:

12/348127

Inventors:

Wladyslaw Walukiewicz - Kensington CA, US
Kin Man Yu - Lafayette CA, US

International Classification:

H01L 31/042
H01L 31/00

US Classification:

136244, 136256

Abstract:

A compositionally graded Group III-nitride alloy is provided for use in a solar cell. In one or more embodiment, an alloy of either InGaN or InAlN formed in which the In composition is graded between two areas of the alloy. The compositionally graded Group III-nitride alloy can be utilized in a variety of types of solar cell configurations, including a single P-N junction solar cell having tandem solar cell characteristics, a multijunction tandem solar cell, a tandem solar cell having a low resistance tunnel junction and other solar cell configurations. The compositionally graded Group III-nitride alloy possesses direct band gaps having a very large tuning range, for example extending from about 0.7 to 3.4 eV for InGaN and from about 0.7 to 6.2 eV for InAlN.