Ziyad Al Tarawneh and Mustafa Muheilan Mu'tah Lil-Buhuth wad-Dirasat, Natural and Applied Sciences Series Vol. 36. No.2, 2021. Abstract: The need to secure affordable renewable energy resources has progressively driven the development of more efficient solar cells over the last few years. Solar cell efficiency enhancement will potentially come from technological developments in solar cell manufacturing by using multi crystalline or amorphous semiconductors rather than traditional single crystal semiconductor solar cells. The alternative is to use SiGe materials in the cell’s structure. The SiGe material is consistent with the established Si technology and is very simple to produce, and can likely provide sufficient conversion performance for inexpensive solar cells. In this paper, the efficiency of the pyramid-based SiGe solar cell is closely investigated. The electrical efficiency improved to 26.5%. Finally, key design parameters affecting the cell’s electrical efficiency such as; Ge content in the SiGe material, SiGe layer thickness, and silicon layer thickness (pyramid height) have been studied.   Keywords: Solar cells, SiGe material, Heterostructure, Ge content