| abstract |
In the gallium nitride-based epitaxial wafer, the off angles of the three points P1, P2, and P3 on the axis Ax are θ1 = 0.2 degrees, θ2 = 0.4 degrees, and θ3 = 0.6 degrees, respectively. Further, the indium composition of the InGaN well layer near the point P1 is larger than the indium composition of the InGaN well layer near the point P3. When the average value of the thickness of the well layer described with reference to FIG. 12 is obtained from three points P1, P2, and P3 on the axis Ax, the value of the average thickness DW1, DW2, DW3 of the well layer is on the axis Ax. Forging increases. Further, the indium composition of the InGaN layer monotonously decreases in the order of the points P1, P2, and P3. Accordingly, a gallium nitride-based epitaxial wafer for providing a semiconductor device having a structure capable of reducing the distribution of light emission wavelengths of an active layer including a well layer formed on a gallium nitride substrate is provided. |