Accession Number : AD0688945

Title :   THE INFLUENCE OF CHEMISORPTION ON THE ELECTRONIC PROPERTIES OF THIN SEMICONDUCTORS: OXYGEN CHEMISORPTION ON THE (11-20) SURFACE OF CdS.

Descriptive Note : Technical rept.,

Corporate Author : PRINCETON UNIV N J DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Goodwin,Thomas A. ; Mark,Peter

Report Date : JUN 1969

Pagination or Media Count : 169

Abstract : A theoretical investigation of the effects of chemisorption surface states on the equilibrium conductivity of thin, wide bandgap semiconductors is presented. Criteria are established for the detection and characterization of chemisorption by electrical measurements on the adsorbent. Measurements with oxygen (acceptor adsorbate) on CdS (n-type adsorbent) confirm the essentials of the theory: (1) There is little or no change in the adsorbent conductivity unless the (pressure dependent) adsorbate surface state concentration exceeds the adsorbent bulk electron density per unit surface area, and the depth of the surface state below the conduction band exceeds the surface potential necessary to completely deplete the adsorbent bulk. (2) Satisfaction of these conditions produce large changes in the electrical properties of the adsorbent on chemisorption, in both the magnitude of the equilibrium conductivity and in its activation energy. A quantitative study of these effects yields the energy level of the adsorbate and the pressure dependent surface state concentration. (Author)

Descriptors :   (*SEMICONDUCTORS, *CHEMISORPTION), (*CADMIUM SULFIDES, ELECTRICAL PROPERTIES), BAND THEORY OF SOLIDS, OXYGEN, SURFACE PROPERTIES, ELECTRICAL CONDUCTIVITY, THESES

Subject Categories : Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE