Patent · US Expired

Growth technique for preparing graded gap semiconductors and devices

US4227948A · kind A · utility

8Cited by
5References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 27, 1977
Grant dateOct 14, 1980
Priority date
Expiry dateDec 27, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/936
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A variable temperature method for the preparation of single and multiple taxial layers of single-phase (e.g., face-centered cubic), ternary lead chalcogenide alloys (e.g., lead cadmium sulfide, [Pb.sub.1-w Cd.sub.w ].sub.a [S].sub.1-a wherein w varies between zero and fifteen hundredths, inclusive, and a=0.500.+-.0.003), deposited upon substrates of barium fluoride, BaF.sub.2, maintained in near thermodynamic equilibrium with concurrently sublimated lead alloy and chalcogenide sources. During preparation, the temperature of the substrate is varied, thereby providing an epilayer with graded composition and predetermined electrical and optical properties along the direction of growth. This growth technique can be used to produce infrared lenses, narrowband detectors, and double heterojunction lasers.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.