Accession Number : ADA138454

Title :   Measuring the Temperature Coefficients of the Elastic Constants of Indium Phosphide.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Poe,J K

PDF Url : ADA138454

Report Date : Dec 1983

Pagination or Media Count : 116

Abstract : The InP technique in this research applies the vibrational theory of small plates developed in order to detect acoustic resonances in single crystal InP. The change in the resonant frequencies allows calculation of the acoustic wave velocity and corresponding effective elastic constant. By measuring the effective elastic constant for various plate orientations, the elastic constants of InP can be derived. Since InP is a cubic crystal with a zinc-blende structure, measurements of the planes are sufficient to compute the elastic constants at a particular temperature. From such computations, changes in the elastic constants can be calculated with respect to temperature. Thus the temperature dependencies for the elastic constants of InP are derived. The circuitry incorporating this InP technique utilizes a spectrum analyzer, an FM DC coupled signal generator, a high precision frequency counter, and a Wayne-Kerr Bridge. In addition, an analog feedback loop was constructed to allow precision within 1 ppm. Such circuitry could easily be modified for automated data processing and high precision. This technique and resulting circuitry could be applicable to measuring acoustic properties on any piezoelectrically excitable material as demonstrated by success on X-cut quartz and InP in this research.

Descriptors :   *Piezoelectric materials, *Indium phosphides, *Elastic properties, *Temperature coefficients, *Acoustic waves, Single crystals, Measurement, Constants, Plates, Semiconductors, Spectrum analyzers, Vibration, Group III compounds, Group V compounds, Electronics, Electronic equipment, Wave propagation, Resonant frequency, Temperature, Theory, Equations, Research management, Theses

Subject Categories : Electrical and Electronic Equipment
      Acoustics
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE