Patent ID: 7943534

Claim:
A semiconductor device manufacturing method comprising simultaneously irradiating a first laser light and a second laser light with a wavelength different from that of the first laser light to a same surface of a semiconductor substrate to perform a thermal processing for activating ion implanted impurity in the semiconductor substrate so that an n-type or p-type diffusion region is formed in the semiconductor, substrate and a temperature of an entire area around the semiconductor substrate in a depth direction is lower than a melting point of the semiconductor substrate, an irradiation time of the first laser light and an irradiation time of the second laser light being controlled so that a temperature distribution in the semiconductor substrate in the depth direction is controlled, wherein: any one of the first laser light and the second laser light is continuous wave laser light, and the other of the first laser light and the second laser light is pulse laser light; the irradiation time of the any one of the first laser light and the second laser light is controlled by adjusting a moving speed and a beam spot size in a moving direction on the semiconductor substrate; and the irradiation time of the other of the first laser light and the second laser light is controlled based on a pulse width.