A Theory of Exciton Photoluminescence for Two Types of Neutral Acceptors in Silicon - A Study of the Systems Si: (B,In), Si: (Al,In), Si: (Ga,In), Si: (B,Al), Si: (B,Ga), and Si: (Al,Ga).

Abstract

Rate equations for the densities of free excitons and excitons bound to two types of neutral acceptors in silicon are solved for steady state in the absence of saturation. These rate equations contain the terms for the tunneling of an exciton bound to one type of neutral impurity to another. The tunneling rates are calculated using a simple model of an exciton in a one-dimensional semi-infinite double potential well. The energy eigenvalue equation for an exciton in this potential well is derived for estimating the exciton tunneling time. The steady-state solutions of the rate equations yield an expression for the ratio of the bound exciton luminescence intensity as a function of the impurity concentrations. The relative photoluminescence intensities for the systems Si:(B,In), Si:(Al,In), Si:(Ga,In), Si(B,Al) Si:(B,Ga), and Si:(Al,Ga) are calculated for various values for the relative free exciton capture cross section ratios. This model predicts no exciton tunneling for any of the above systems for the low impurity concentration range. For the systems with large differences in the bound exciton energy levels such as Si:(B,In), Si:(Al,In), and Si:(Ga,In), it predicts quenching of shallow impurity bound exciton luminescence. For the systems with small differences in the bound exciton energy levels such as Si:(B,Al) and Si:(B,Ga), the theory predicts enhancement of shallow impurity bound exciton luminescence. For the system Si:(Al,Ga) in which the difference in the bound exciton energy levels is very small, gallium bound exciton luminescence dominates if the aluminum free exciton capture section is less than the gallium free exciton capture cross section.

Document Details

• Document Type: Technical Report
• Publication Date: Feb 01, 1985
• Accession Number: ADA155452

Entities

People

• D. H. Brown
• D. S. Moroi
• M. C. Ohmer

Organizations

• University of Dayton

Tags

Communities of Interest

• Advanced Electronics

DTIC Thesaurus Topics

• Abstracts
• Aeronautical Laboratories
• Air Force
• Energy Levels
• Equations
• Impurities
• Luminescence
• Materials
• Materials Laboratories
• Optical Materials
• Oscillators
• Photoluminescence
• Quantum Tunneling
• Security
• Semiconductors
• Steady State
• Tunneling

Readers

• Aerospace Propulsion Engineering.
• Chemistry (specifically Chemical Fluorescence)
• Thin Film Deposition Science.

Technology Areas

• Microelectronics