Patent ID: 8529697
Filing Date: 2013-09-10
Classification: C30B,H01L,Y10T

Abstract:
1. A process for growing a crystal of a nitride semiconductor which comprises: the step of mounting a substrate in a reaction tube, the step of feeding a first material gas containing a Group 3 element onto the substrate in the reaction tube, and the step of feeding a second material gas containing elemental nitrogen onto the substrate in the reaction tube, said feeding steps being carried out alternately to deposit a nitride semiconductor crystal directly on the substrate, wherein, the number of moles of the elemental nitrogen contained in the second material gas has a ratio of 200 or more to the number of moles of the Group 3 element in the first material gas until the film thickness of the nitride semiconductor crystal deposited on the substrate reaches a critical film thickness, whereas the number of moles of the elemental nitrogen contained in the second material gas has a ratio of less than 200 to the number of moles of the Group 3 element in the first material gas when the film thickness is equal to, or over the critical film thickness, said critical film thickness defined as the thickness of the film at which dislocations occur.