MEASUREMENT OF ENERGY-LOSS FROM A HEMT STRUCTURE BY OBSERVING EMITTED PHONONS


Wigmore J., Erol M., SAHRAOUITAHAR M., ARI M. , Wilkinson C., Davies J., ...More

SEMICONDUCTOR SCIENCE AND TECHNOLOGY, vol.8, no.3, pp.322-326, 1993 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 8 Issue: 3
  • Publication Date: 1993
  • Doi Number: 10.1088/0268-1242/8/3/003
  • Title of Journal : SEMICONDUCTOR SCIENCE AND TECHNOLOGY
  • Page Numbers: pp.322-326

Abstract

Using nanosecond heat pulse techniques we have observed both acoustic and optic phonon emission by the hot 2DEG in GaAs/AlGaAs HEMT structures. Both transverse and longitudinal modes were detected in the optic regime but only transverse in the acoustic regime. The ability to vary carrier density allowed us to eliminate the effect of contact resistance and hence to determine absolutely the power level at which energy loss took place equally via acoustic and optic phonons. The figure obtained was 2.3 +/- 0.5 pW per electron, inconsistent with a model of acoustic emission based simply on deformation potential coupling, suggesting the presence of an additional source of inelastic scattering.