PECULIARITIES OF THE OPTOELECTRONIC CHARACTERISTICS OF DOUBLE-BARRIER STRUCTURES

Abstract

The photoelectronic processes occurring in a selectively photosensitive 
semiconductor p + - n - p + structure are investigated. In it, the n - base is an active 
medium occupied by oppositely directed potential barriers. With the help of 
modulation of the external voltage of the width of the barriers one at the expense of the 
other, a possibility of selective spectral sensitivity and appearance of a change in the 
sign of the spectral photocurrent as a result of this modulation is created. 
The relationships between the photoelectronic processes occurring in the 
photodetector and the structural parameters are analyzed. The selective spectral 
photosensitivity of the optical signal is theoretically and experimentally substantiated. 
An algorithm, taking into account the most complete cause-and-effect relationships in 
obtaining the spectral dependence of the intensity of the absorbed radiation is 
considered. Its testing under the influence of white LED radiation is carried out, the 
physical processes due to the peculiarity of the capacitance-voltage characteristics and 
the possibility of determining the difference in the heights of potential barriers using 
these characteristics are explained. 
The results open up prospects for the creation of photodetectors with new 
functional capabilities and, on their basis, multifunctional devices for the analysis of 
optical radiation. Optical devices will be eliminated in them, numerous photodiodes 
will be replaced by one photodetector, which has a low noise level and high threshold 
sensitivity. This, in its turn, opens up the prospect of analyzing the spectrum of weak 
signals necessary in the study, for example, of weak radiation from distant stars, as well 
as the possibility of solving problems related to human health, biological and ecological 
safety, climate change, monitoring of water and food, etc.