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Low Pressure Source for Mass-Selective, Diffusion Assisted Epitaxy

Award Information

Department of Defense
Air Force
Award ID:
Program Year/Program:
2002 / STTR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
SVT Associates, Inc.
7620 executive drive eden prairie, MN 55344
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Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2002
Title: Low Pressure Source for Mass-Selective, Diffusion Assisted Epitaxy
Agency / Branch: DOD / USAF
Contract: F49620-02-C-0061
Award Amount: $99,994.00


Dramatic differences in the diffusivities of the constituents of novel thin film materials and structures limit material perfection under far from equilibrium growth conditions. We will develop a new light-mass ion source, compatible with the low pressurerequirements of molecular beam epitaxy (MBE), to provide selective enhancement of the motion of surface atoms. Helium or hydrogen ions incident on a surface at approximately 100 eV will mainly transfer their energy to lower mass, surface atoms. Thislow-pressure ion source will be compared to a higher pressure Kaufman source for the MBE growth of technologically important III-nitride materials. The low-mass ions will overwhelmingly deposit their energy at the N atoms, effectively setting the growthconditions closer to equilibrium. The results will be compared to literature reports using higher mass ions. For low-mass ions incident at low angles with low energy, the energy transfer will be well below sputtering thresholds. The impinging ions willonly be able to excite local phonon modes that selectively enhance surface diffusion. If more momentum transfer is desired, higher mass ions could be used. Development of this new ion source would greatly impact a wide range of materials systems.Currently, the growth of multicomponent thin films and films with hyperabrupt interfaces challenges all growth techniques. The proposed low-mass ion source will allow control of defects, grain size, surface chemistry, and enable abrupt hetero-epitaxialcombinations not currently possible. As a proof of concept, the enhanced MBE growth of GaN and InGaN will be demonstrated. This technique would greatly benefit the development of novel semiconductor thin films and structures.

Principal Investigator:

Amir M. Dabiran
MBE Lab Manager

Business Contact:

Jane Marks
Project Manager
Small Business Information at Submission:

Svt Assoc., Inc.
7620 Executive Drive Eden Prairie, MN 55344

EIN/Tax ID: 411764876
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Research Institution Information:
University of Minnesota
Dept. of Elec. & Comp. Eng., 200 Union Street SE, Room 4-17
Minneapolis, MN 55455
Contact: Philip I. Cohen
Contact Phone: (612) 625-5517
RI Type: Nonprofit college or university