The self-compression of injected electron-hole plasma in silicon

TL;DR

This paper investigates the self-compression of injected electron-hole plasma in silicon, revealing plasma condensation phenomena and their effects on luminescence and energy gap reduction at temperatures above 300 K.

Contribution

It introduces the concept of plasma self-compression in silicon and links it to observed luminescence behavior and energy gap reduction, providing new insights into plasma dynamics in semiconductors.

Findings

High internal quantum efficiency of 0.003 in luminescence

Observation of threshold optical hysteresis

Evidence of plasma self-compression phenomena

Abstract

A recombination radiation line of electron-hole plasma, observed in electroluminescence spectra of tunneling silicon MOS diodes, has been investigated at the temperature > 300 K. The internal quantum efficiency of the luminescence, equal to 0.003, appears to be unexpectedly high. The spectral position of the luminescence line indicates, that a weak overheating of the diode by the diode current results in an anomalously strong reduction of the semiconductor energy gap inside the electron-hole plasma. A unique threshold optical hysteresis is observed in the luminescence intensity with changing diode current. These results are explained by condensation of injected electron-hole plasma into a dense state. A reduction of the semiconductor energy gap due to generation of phonons by the plasma is discussed as a reason of the plasma condensation. The plasma condensation is identified as the plasma self-compression.