Top Limit Characteristics of New Type Cascade PC on the Basis of Homogeneous Semiconductor

A new type homogeneous planar PC （photoelectric converter） on the basis of multijunction semiconductor n＋-p-p＋-n＋-p-p＋-...-n＋-p-p＋ structure has been investigated. The entire structure is a cascade PC consisting of a number of elements of the structure--single PCs connected in series and illuminated by light that has consistently passed through the previous semiconductor layers. The theory of converter of both monochromatic and solar radiation has been developed and the limiting values of their photoelectric and power characteristics have been determined, including the optimal thickness and number of single PCs layered on a base PC, their spectral sensitivity, current-voltage characteristics and efficiency. The open-circuit voltage grows practically linearly with the number of elements in the cascade. The top efficiency limit for a certain optimal elements number reaches its maximum that exceeds considerably that of the base PC, especially in the range of low collecting coefficient of charge carriers in the base PC.