Accession Number : ADA299965

Title :   II-VI/III-V Heterojunctions.

Descriptive Note : Final rept. 1 Aug 92-31 Jul 95,

Corporate Author : PURDUE UNIV LAFAYETTE IN SCHOOL OF ELECTRICAL ENGINEERING

Personal Author(s) : Gunnshor, Robert L.

PDF Url : ADA299965

Report Date : 31 JUL 1995

Pagination or Media Count : 40

Abstract : Use of the Mg containing quaternary led to a pseudomorphic SCH laser. The graded bandgap ohmic contact reduced threshold voltages to 5 volts as room temperature cw was obtained. TEM studies provided the first reports of compositional modulation in a II-VI alloy. It was found that the quaternary above a certain bandgap exhibited a compositional modulation in a particular <110> direction. Laser degradation has been studied using electroluminescence microscopy and TEM of degraded devices. The microstructural analysis revealed that the degradation originated from stacking faults nucleated at or near the II-VI/III-V interface. Using etching techniques it was determined that room temperature cw lasers had stacking fault densities of 3x10(exp 5) to 1x10(exp 6)/sq cm. Recently we have emphasized reducing these densities. We have reached the 10(exp3)/sq cm and are consistently in the low 10(exp 4)/sq cm. It appears that the high resistivity observed in p-type wide bandgap alloys is the manifestation of a DX-like behavior. Although previous studies reported DX centers in many n-type semiconductors there are no previous report for acceptors in any p-type semiconductor; we named this phenomenon an AX center.

Descriptors :   *MAGNESIUM, *HETEROJUNCTIONS, *LASERS, *GROUP III COMPOUNDS, *GROUP V COMPOUNDS, *GROUP II-VI COMPOUNDS, DENSITY, MICROSTRUCTURE, DEGRADATION, INTERFACES, RESISTANCE, ELECTROLUMINESCENCE, STRUCTURAL ANALYSIS, VOLTAGE, ENERGY GAPS, SEMICONDUCTORS, NUCLEATION, ALLOYS, ETCHING, ROOM TEMPERATURE, MICROSCOPY, BROADBAND, N TYPE SEMICONDUCTORS, ELECTRON ACCEPTORS, MODULATION, COMPOSITION(PROPERTY), STACKING, P TYPE SEMICONDUCTORS, CONTINUOUS WAVE LASERS, FAULTS.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Electrical and Electronic Equipment
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE