Yuan Li

US Patent:

6351581, Feb 26, 2002

Filed:

Mar 17, 1998

Appl. No.:

09/040477

Inventors:

Christopher Richard Doerr - Middletown NJ
Yuan P. Li - Duluth GA

Assignee:

Agere Systems Optoelectronics Guardian Corp. - Orlando FL

International Classification:

G02B 626

US Classification:

385 24, 359124

Abstract:

An optical add-drop multiplexer (ADM) avoids waveguide crossings by being constructed in the form of a Mach-Zehnder interferometer having a demultiplexer/multiplexer (demux/mux) pair in each of its arms. Each demux/mux pair is interconnected by coherent connecting paths having heating elements for increasing the path length of selected connecting paths. Waveguide optical couplers having asymmetric transfer functions are used at the input and output of the ADM. These couplers cooperate with the activated heating elements to add and/or delete a selected optical channel to/from an optical transmission path. Each coherent connecting path includes a number of waveguides. The end-to-end transmission characteristic of the ADM through each individual waveguide has a Gaussian shape. These Gaussian shapes are designed intersect at their -3 dB wavelengths so that the end-to-end transmission characteristic of the ADM is flat.

US Patent:

6539149, Mar 25, 2003

Filed:

Sep 20, 1999

Appl. No.:

09/399575

Inventors:

Giovanni Barbarossa - Tucker GA
Leonard George Cohen - Atlanta GA
Yuan P. Li - Duluth GA
Yan Wang - Norcross GA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 634

US Classification:

385 37, 359571

Abstract:

In accordance with the invention, an optical router for an optical communications system comprises a pair of transmissive Echelle gratings having their grating surfaces coupled by a waveguide grating. The arrangement provides for substantial design freedom in that the dispersive parameters include the shapes of the first and second Echelle gratings as well as the path length difference among the waveguides. Moreover the device eliminates any need for reflective surfaces in the Echelle gratings.

US Patent:

6658181, Dec 2, 2003

Filed:

Jan 2, 2002

Appl. No.:

10/038508

Inventors:

Yan Wang - Norcross GA
Yuan P. Li - Duluth GA

Assignee:

Wavesplitter Technologies, Inc. - Fremont CA

International Classification:

G02B 612

US Classification:

385 37, 385 24, 385 27, 385 14

Abstract:

A method and apparatus provides a WDM optical signal having a plurality of channels with a pair-wise orthogonal polarization state. The method begins by receiving a plurality of unpolarized optical wavelengths defining a plurality of optical channels separated by a prescribed channel spacing. A polarization wavelength dependent shift is imparted to the optical wavelengths, which is substantially equal to a particular fraction of the prescribed channel spacing.

US Patent:

6888238, May 3, 2005

Filed:

Jul 9, 2003

Appl. No.:

10/616858

Inventors:

Yuan Li - Sunnyvale CA, US

Assignee:

Altera Corporation - San Jose CA

International Classification:

H01L023/34

US Classification:

257706

Abstract:

A semiconductor package includes a chip carrier to receive a semiconductor with a dimension generally greater than 22 mm. The chip carrier has a first coefficient of thermal expansion that is larger than the coefficient of thermal expansion of the semiconductor. A heat spreader having parallel channels on opposite sides is attached to the chip carrier along the channels. The heat spreader has a second coefficient of thermal expansion that is smaller than or equal to the coefficient of thermal expansion of the chip carrier. The interplay between the heat spreader and the chip carrier can effectively reduce package warpage and maintain coplanarity within the specification.

US Patent:

6909176, Jun 21, 2005

Filed:

Nov 20, 2003

Appl. No.:

10/719451

Inventors:

Wen-Chou Vincent Wang - Cupertino CA, US
Donald S. Fritz - San Jose CA, US
Yuan Li - Sunnyvale CA, US

Assignee:

Altera Corporation - San Jose CA

International Classification:

H01L023/10

US Classification:

257706, 257701, 257783, 257775

Abstract:

Provided are a semiconductor low-K Si die flip chip package with warpage control and fabrication methods for such packages. The packages include heat spreaders that are attached to the low-K Si die and packaging substrate. In general, the modulus of the thermal interface material, which is used to attach the heat spreader to the low-K Si die, is selected as high as possible relative to other commercially available thermal interface materials. On the other hand, the modulus of the adhesive, which is used to attach the heat spreader via an optional stiffener to the substrate, is selected as low as possible relative to other commercially available adhesives. The result is a package with less bowing and so improved co-planarity (in compliance with industry specifications) with the surface to which it is ultimately bound. Moreover, the low-K Si die and package reliabilities are thereby enhanced.

US Patent:

6917760, Jul 12, 2005

Filed:

Dec 31, 2001

Appl. No.:

10/039242

Inventors:

Yuan P. Li - Duluth GA, US
Yan Wang - Norcross GA, US
Kevin Sullivan - Fremont CA, US

Assignee:

Wavesplitter Technologies, Inc. - Fremont CA

International Classification:

H04B010/00

US Classification:

398 82, 398 48

Abstract:

A method and apparatus is provided for reformatting or interleaving a WDM signal that includes a plurality of optical channels having a first bandwidth and a first channel spacing. The method begins by receiving the WDM signal and dividing it into first and second subsets of optical channels each having a second channel spacing. Next, the first subset of optical channels are divided into third and fourth subsets of optical channels each having a third channel spacing. In addition, the second subset of optical channels is divided into fifth and sixth subsets of optical channels each having a fourth channel spacing. The third and fifth subsets of optical channels are combined to generate a first output WDM signal, while the fourth and sixth subsets of optical channels are combined to generate a second output WDM signal.

US Patent:

7006729, Feb 28, 2006

Filed:

Dec 31, 2001

Appl. No.:

10/039245

Inventors:

Yan Wang - Norcross GA, US
Yuan P. Li - Duluth GA, US

Assignee:

Wavesplitter Technologies, Inc. - Fremont CA

International Classification:

G02B 6/34
G02B 6/26

US Classification:

385 37, 385 46

Abstract:

An optical device is provided which includes a slab waveguide and at least one input waveguide coupled to a first side of the slab waveguide. The device also includes a plurality of output waveguides coupled to a second side of the slab waveguide. The slab waveguide has a segmented transition region that includes a plurality of waveguiding regions spaced apart from one other by at least one discrete sector.

US Patent:

7009307, Mar 7, 2006

Filed:

May 19, 2004

Appl. No.:

10/849651

Inventors:

Yuan Li - Sunnyvale CA, US

Assignee:

Altera Corporation - San Jose CA

International Classification:

H01L 23/48
H01L 23/52
H01L 29/40

US Classification:

257783, 257707, 438118

Abstract:

Provided are a semiconductor die flip chip package with warpage control and fabrication methods for such packages. The packages include heat spreaders that are attached to the die and packaging substrate. In general, the modulus of the adhesive, which is used to attach the heat spreader to the substrate, is selected to provide a relatively “soft” connection. The result is a package with less bowing and so improved co-planarity (e. g. , in compliance with industry specifications) with the surface to which it is ultimately bound. Moreover, the die and package reliabilities are thereby enhanced.