Patent ID: 8222128

Claim:
A method for introducing impurities, comprising: a first step for irradiating a plasma containing He to a surface of a substrate so as to form an amorphous layer at the surface of the substrate, wherein an irradiating time regarding the plasma is not shorter than 5 second (inclusive) and shorter than 70 second (inclusive), and the substrate is a single crystalline silicon substrate, a second step for introducing impurities into the surface of the substrate, wherein the second step is a step for plasma-doping the impurities, and an annealing step after the second step, wherein the first step is performed at the same time as the second step, the annealing step is a step for activating the impurities, and a bias voltage in time of irradiating the plasma is more than 30V (inclusive) and less than 310V (inclusive).