ESR Centers and Charge Defects Near the Silicon/Silicon Dioxide Interface.
Abstract
The Nishi-B esr center has been examined as a function of thermal oxidation and annealing conditions in single-crystal silicon wafers. It was observed that B concentration was not correlated with fixed surface-state charge density Q, despite some similarities in their behavior. In freshly oxidized wafers, B typically ranges up to 200 per nm sq, and Q up to 50 per nm sq. The concentration of B is highly dependent on cooling rates; concentration does not depend on oxide thickness and B may be observed even in native oxides. The g-value of the orientation-averaged B signal (2.0064) favors its assignment to trivalent Si in a silicon environment, as in crushed silicon (2.0055), rather than to the well-studied E centers (2.0008) found in various forms of damaged silicon dioxide. In our thermal oxides, E centers were unobservable, and thus cannot be the main source of Q, despite their nominal positive charge. Preliminary evidence shows a correlation of B with initial, unannealed fast interface states N, supporting the idea that trivalent Si is the origin of these states. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1978
- Accession Number
- ADA056582
Entities
People
- Edward H. Poindexter
- Edwin R. Ahlstrom
- Philip J. Caplan
Organizations
- United States Army Communications-Electronics Command