GROUP III-NITRIDE SOLAR CELL WITH GRADED COMPOSITIONS

摘要

A compositionally graded Group Ill-nitride alloy is provided for use in a solar cell. In one or more embodiment, an alloy of either InGaN or InAIN formed in which the In composition is graded between two areas of the alloy. The compositionally graded Group Ill-nitride alloy can be utilized in a variety of types of solar cell configurations, including a single P-N junction solar cell having tandem solar cell characteristics, a multijunction tandem solar cell, a tandem solar cell having a low resistance tunnel junction and other solar cell configurations. The compositionally graded Group Ill-nitride alloy possesses direct band gaps having a very large tuning range, for example extending from about 0.7 to 3.4 eV for InGaN and from about 0.7 to 6.2 eV for InAIN.