SEMICONDUCTOR EPITAXIAL STRUCTURE AND METHOD OF FORMING THE SAME

The present invention provides a semiconductor epitaxial structure and a method of forming the same. The semiconductor epitaxial structure including a nucleation layer disposed on a substrate; a buffer layer disposed on the nucleation layer; a semiconductor layer disposed on the buffer layer; a barrier layer disposed on the semiconductor layer; and a cap layer disposed on the barrier layer. In a case where a bowing of the semiconductor epitaxial structure is less than or equal to +/-30 [mu]m, a maximum value or a minimum value of a ratio of a thickness of the buffer layer to a thickness of thesemiconductor layer is represented as following formula: Y=aX1-bX2+cX3, X1>=0 nm, X2>=750 nm, X3>=515 nm, wherein X1 is a thickness of the nucleation layer, X2 is the thickness of the buffer layer, X3 is the thickness of the semiconductor layer, a, b and c are constants respectively, and Y is a ratio of X3 to X2. 一种半导体外延结构及其形成方法，所述半导体外延结构包括：成核层配置在基板上；缓冲层配置在成核层上；半导体层配置在缓冲层上；阻障层配置在半导体层上；以及顶盖层配置在阻障层上。在半导体外延结构的翘曲率小于等于+/-30微米