Patent ID: 7442631

Claim:
A doping method comprising the steps of: obtaining a proportion X (0<X<1) of ions of a compound including a donor impurity or an acceptor impurity in total ions from mass spectrum by generating plasma using a first source gas in which the compound including the donor impurity or the acceptor impurity is diluted with a diluent gas made of hydrogen or a rare gas to a first concentration of 5% to 40% in an ion doping apparatus, analyzing a peak concentration Y of the compound including the donor impurity or the acceptor impurity in a first processing object which is doped with the ions of the compound including the donor impurity or the acceptor impurity by the ion doping apparatus using a second source gas in which the compound including the donor impurity or the acceptor impurity is diluted with the diluent gas to a second concentration lower than the first concentration, referring to a dose amount of total ions as D 0 and setting an acceleration voltage at a value, obtaining a dose amount D 1 of total ions from a relational expression, Y=(D 1 /D 0 )(aX +b), wherein a and b are assumed to be real numbers, and doping a second processing object with the donor impurity or the acceptor impurity by the ion doping apparatus using a third source gas, wherein a dose amount of total ions is set at D 1 , and an acceleration voltage is set at the value.