1. 2 New Materials and Concepts for Cells and Modules
Keywords:
Tandem, High Efficiency, Heterojunction, Multijunction Solar Cell, Novel Concepts
Summary / Abstract:
Conventional solar cells, including multijunction solar cells, are based on pn junctions as building blocks. In contrast, the three-terminal heterojunction bipolar transistor solar cell (3T–HBTSC) explores the use of a bipolar transistor structure to build a solar cell. The limiting efficiency of this transistor structure equals that of a double-junction solar cell. However, since the 3T–HBTSC does not require tunnel junctions, its minimal structure has only three semiconductor layers, while the minimal structure of a double junction solar cell has six. This work reviews the fundamental theory of this solar cell and the steps carried out towards its practical implementation.