Method of digital epitaxy by externally controlled closed-loop feedback

Patent · Tue Jul 19 00:00:00 EDT 1994

OSTI ID:6983545

Eres, D; Sharp, J W

A method and apparatus for digital epitaxy are disclosed. The apparatus includes a pulsed gas delivery assembly that supplies gaseous material to a substrate to form an adsorption layer of the gaseous material on the substrate. Structure is provided for measuring the isothermal desorption spectrum of the growth surface to monitor the active sites which are available for adsorption. The vacuum chamber housing the substrate facilitates evacuation of the gaseous material from the area adjacent the substrate following exposure. In use, digital epitaxy is achieved by exposing a substrate to a pulse of gaseous material to form an adsorption layer of the material on the substrate. The active sites on the substrate are monitored during the formation of the adsorption layer to determine if all the active sites have been filled. Once the active sites have been filled on the growth surface of the substrate, the pulse of gaseous material is terminated. The unreacted portion of the gas pulse is evacuated by continuous pumping. Subsequently, a second pulse is applied when availability of active sites is determined by studying the isothermal desorption spectrum. These steps are repeated until a thin film of sufficient thickness is produced. 4 figs.

• DOE Contract Number: AC05-84OR21400
• Assignee: Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)
• Patent Number(s): US 5330610; A
• Application Number: PPN: US 8-068027
• OSTI ID: 6983545
• Resource Relation: Patent File Date: 28 May 1993
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MATERIALS
VAPOR PHASE EPITAXY
CLOSED-LOOP CONTROL
PROCESS CONTROL
VACUUM SYSTEMS
CONTROL
EPITAXY
360101* - Metals & Alloys- Preparation & Fabrication
360201 - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360601 - Other Materials- Preparation & Manufacture