Christine Wang

US Patent:

20030037874, Feb 27, 2003

Filed:

Jul 26, 2002

Appl. No.:

10/205704

Inventors:

Christine Wang - Bedford MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

C09J001/00
B32B031/00
C09J005/00

US Classification:

156/306300, 156/281000

Abstract:

In bonding a first crystalline semiconductor substrate to a second crystalline semiconductor substrate, a liquid is applied to a first surface of the first substrate and to a first surface of the second substrate to wet both substrate first surfaces. The first surface of the first substrate is brought together with the first surface of the second substrate while the liquid substantially remains on both first surfaces, and then the liquid is evaporated from the substrate first surfaces, while the substrate first faces are together, at an evaporation temperature that is below the boiling point of the liquid at ambient pressure. The substrates are then heat treated at a temperature above the evaporation temperature. Surface channels can be formed in a first surface of at least one of the first and second substrates, and during the heat treatment, a crystal growth promotion vapor can be supplied to the substrates.

US Patent:

20140027708, Jan 30, 2014

Filed:

Jul 25, 2013

Appl. No.:

13/951240

Inventors:

Christian Pfluegl - Medford MA, US
Christine A. Wang - Bedford MA, US
Mark Francis Witinski - Cambridge MA, US

Assignee:

EOS Photonics, Inc. - Cambridge MA
Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01L 29/15

US Classification:

257 9, 438478

Abstract:

Photonic integrated circuits (PICs) are based on quantum cascade (QC) structures. In embodiment methods and corresponding devices, a QC layer in a wave confinement region of an integrated multi-layer semiconductor structure capable of producing optical gain is depleted of free charge carriers to create a low-loss optical wave confinement region in a portion of the structure. Ion implantation may be used to create energetically deep trap levels to trap free charge carriers. Other embodiments include modifying a region of a passive, depleted QC structure to produce an active region capable of optical gain. Gain or loss may also be modified by partially depleting or enhancing free charge carrier density. QC lasers and amplifiers may be integrated monolithically with each other or with passive waveguides and other passive devices in a self-aligned manner. Embodiments overcome challenges of high cost, complex fabrication, and coupling loss involved with material re-growth methods.

US Patent:

52166848, Jun 1, 1993

Filed:

Sep 7, 1990

Appl. No.:

7/579347

Inventors:

Christine A. Wang - Bedford MA
James N. Walpole - Concord MA
Hong K. Choi - Concord MA
Joseph P. Donnelly - Carlisle MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01S 319

US Classification:

372 45

Abstract:

A strained quantum-well diode laser with an AlInGaAs active layer and AlGaAs cladding and/or confining layers on a GaAs substrate is provided. AlInGaAs/AlGaAs lasers can be configured in laser geometries including ridge, waveguide, buried heterostructure, oxide-defined, proton-defined, narrow-stripe, broad-stripe, coupled-stripe and linear arrays using any epitaxial growth technique. Broad-stripe devices were fabricated in graded-index separate confinement heterostructures, grown by organometallic vapor phase epitaxy on GaAs substrates, containing a single Al. sub. y In. sub. x Ga. sub. l-x-y As quantum well with x between 0. 14 and 0. 12 and y between 0. 05 and 0. 17. With increasing Al content, emission wavelengths from 890 to 785 nm were obtained. Threshold current densities, J. sub. th 's, less than 200 A cm. sup.

US Patent:

49568442, Sep 11, 1990

Filed:

Mar 17, 1989

Appl. No.:

7/325292

Inventors:

William D. Goodhue - Chelmsford MA
Kurt Rauschenbach - Marlboro MA
Christine A. Wang - Bedford MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01S 300

US Classification:

372 44

Abstract:

An improved two-dimensional semiconductor surface-emitting laser array is described in which two intra-cavity internal reflecting surfaces are formed at a 45. degree. angle to the plane of the active layer of the semiconductor laser so as to internally reflect light from each end of the active layer in a direction normal to the plane of the active layer with a buried reflective mirror provided in the path of one of said reflections, so as to transmit reflected light back through the laser and out the top surface of the array.

US Patent:

49976770, Mar 5, 1991

Filed:

Aug 31, 1987

Appl. No.:

7/091268

Inventors:

Christine A. Wang - Bedford MA
Robert A. Brown - Winchester MA
James W. Caunt - Concord MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

C23C 1600

US Classification:

4272481

Abstract:

A gaseous mixture is introduced through a radial inlet into a plenum-like antichamber above a porous diaphragm mounted across the top of a reactor vessel of substantially uniform width. The antichamber and diaphragm are substantially coextensive with the width of the vessel. The diaphragm may form part of a removable cover/diaphragm unit received in a collar-like ring. The substrate holder includes a molybdenum cap and base which fits over a pedestal of refractory material carrying a temperature sensor with an electrical lead extending down the hollow core of a rotatable reactor The Government has rights in this invention pursuant to Contract Number F19628-85-C-0002 awarded by the Department of the Air Force.

US Patent:

52608220, Nov 9, 1993

Filed:

Jan 31, 1992

Appl. No.:

7/829778

Inventors:

Leo J. Missaggia - Milford MA
Christine A. Wang - Bedford MA
Stephen R. Chinn - Westford MA
Emily S. Kintzer - Arlington MA
James N. Walpole - Concord MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01S 319
H01L 3300

US Classification:

359337

Abstract:

A semiconductor laser gain structure having a tapered gain region comprising cavity spoilers for receiving light which is reflected off of the output facet back into the semiconductor and removing it from the gain region so as to reduce or eliminate self oscillation. The boundaries of the gain region are also designed to have a very low refractive index gradient so as to minimize reflection of light off of the boundaries back into the gain region. The gain structure may be embodied in a semiconductor laser oscillator or semiconductor laser amplifier depending on whether the input facet is or is not, respectively, anti reflection coated. The output facet is anti-reflection coated in either embodiment.

US Patent:

55555446, Sep 10, 1996

Filed:

Apr 4, 1994

Appl. No.:

8/222413

Inventors:

James N. Walpole - Concord MA
Emily S. Kintzer - Arlington MA
Stephen R. Chinn - Westford MA
Christine A. Wang - Bedford MA
Lee J. Missaggia - Milford MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01S 318

US Classification:

372 50

Abstract:

A semiconductor laser oscillator structure and method is described having a tapered gain region in one-half of a laser cavity and a confocal oscillator region in another half of the cavity. An aperture is formed between two pairs of cavity spoilers located between the two cavity halves. One pair of spoilers is provided for receiving light which is reflected off of an output facet back into the semiconductor and removing it from the gain region. The other pair of spoilers removes light reflected from a curved mirror surface formed at the end of the other laser cavity half.

US Patent:

54003539, Mar 21, 1995

Filed:

Nov 8, 1993

Appl. No.:

8/148386

Inventors:

James N. Walpole - Concord MA
Emily S. Kintzer - Arlington MA
Stephen R. Chinn - Westford MA
Christine A. Wang - Bedford MA
Leo J. Missaggia - Milford MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H01S 319

US Classification:

372 46

Abstract:

A semiconductor laser gain structure having a tapered gain region comprising cavity spoilers for receiving light which is reflected off of the output facet back into the semiconductor and removing it from the gain region so as to reduce or eliminate self-oscillation. The boundaries of the gain region are also designed to have a very low refractive index gradient so as to minimize reflection of light off of the boundaries back into the gain region. The gain structure may be embodied in a semiconductor laser oscillator or semiconductor laser amplifier depending on whether the input facet is or is not, respectively, anti-reflection coated. The output facet is anti-reflection coated in either embodiment.