| abstract |
In an oriented polycrystalline group 13 element nitride free-standing substrate, the tilt angle of single crystal particles is reduced and the variation in tilt angle is reduced. A self-supporting substrate is made of polycrystalline group 13 element nitride composed of a plurality of single crystal grains oriented in a specific crystal orientation in a substantially normal direction. The free-standing substrate has a top surface and a bottom surface. The polycrystalline group 13 element nitride is made of gallium nitride, aluminum nitride, indium nitride or a mixed crystal thereof, and contains zinc at a concentration of 1 × 10 17 atoms / cm 3 or more and 1 × 10 20 atoms / cm 3 or less. . [Selection] Figure 2 |