System for monitoring the growth of crystalline films on stationary substrates

Patent · Tue Dec 31 04:00:00 EST 1996

OSTI ID:415756

Sheldon, P.

A system for monitoring the growth of crystalline films on stationary or rotating substrates includes a combination of some or all of the elements including a photodiode sensor for detecting the intensity of incoming light and converting it to a measurable current, a lens for focusing the RHEED pattern emanating from the phosphor screen onto the photodiode, an interference filter for filtering out light other than that which emanates from the phosphor screen, a current amplifier for amplifying and convening the current produced by the photodiode into a voltage, a computer for receiving the amplified photodiode current for RHEED data analysis, and a graphite impregnated triaxial cable for improving the signal to noise ratio obtained while sampling a stationary or rotating substrate. A rotating stage for supporting the substrate with diametrically positioned electron beam apertures and an optically encoded shaft can also be used to accommodate rotation of the substrate during measurement. 16 figs.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-83CH10093
• Assignee: Midwest Research Inst., Kansas City, MO (United States)
• Patent Number(s): US 5,588,995/A/
• Application Number: PAN: 8-434,181
• OSTI ID: 415756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL GROWTH
DATA ACQUISITION SYSTEMS
DESIGN
MONITORING
MONITORS
OPTICAL FILTERS
SEMICONDUCTOR MATERIALS