Method of forming semiconductor film

Claim 1

A method of simultaneously forming semiconductor films on a plurality of substrates, comprising the steps of: preparing a first treatment gas, the first treatment gas providing a main material of the semiconductor films as a result of thermal decomposition; preparing a second treatment gas, the second treatment gas providing an impurity, with which the semiconductor films are doped, as a result of thermal decomposition; heating a reaction tube; loading the substrates into the reaction tube; reducing pressure in the reaction tube; supplying the reaction tube with the first and second treatment gases at first and second flow rates, respectively, thereby forming first layer on each of the substrates, the first layer containing the impurity of a first density; supplying the reaction tube with the first and second treatment gases at third and fourth flow rates, respectively, thereby forming a second layer on the first layer, the second layer containing the impurity of a second density sufficiently higher than the first density; supplying the reaction tube with the first and second treatment gases at fifth and sixth flow rates, respectively, thereby forming third layer on the second layer, the third layer containing the impurity of a third density sufficiently lower than the second density; and diffusing the impurity contained in the second layer into the first and third layers by heating the first through third layers, thereby making an integral film of uniform impurity density from the first through third layers.

Claim 2

A method of simultaneously forming semiconductor films on a plurality of substrates, comprising the steps of: preparing a first treatment gas, the first treatment gas providing a main material of the semiconductor films as a result of thermal decomposition; preparing a second treatment gas, the second treatment gas providing an impurity, with which the semiconductor films are doped, as a result of thermal decomposition; heating a reaction tube; loading the substrates into the reaction tube; reducing pressure in the reaction tube; supplying the reaction tube with the first and second treatment gases at first and second flow rates, respectively, thereby forming first layer on each of the substrates, the first layer containing the impurity of a first density; supplying the reaction tube with the first and second treatment gases at third and fourth flow rates, respectively, thereby forming a second layer on the first layer, the second layer containing the impurity of a second density sufficiently higher than the first density; supplying the reaction tube with the first and second treatment gases at fifth and sixth flow rates, respectively, thereby forming third layer on the second layer, the third layer containing the impurity of a third density sufficiently lower than the second density; and diffusing the impurity contained in the second layer into the first and third layers by heating the first through third layers, thereby making an integral film of uniform impurity density from the first through third layers.

Claim 11

A method of forming a semiconductor film on a substrate, comprising the steps of: preparing a first treatment gas, the first treatment gas providing a main material of the semiconductor film as a result of thermal decomposition; preparing a second treatment gas, the second treatment gas providing an impurity, with which the semiconductor film is doped, as a result of thermal decomposition; heating a reaction tube; loading the substrate into the reaction tube; reducing pressure in the reaction tube; supplying the reaction tube with the first and second treatment gases at first and second flow rates, respectively, thereby forming first layer on the substrate, the first layer containing the impurity of a first density; supplying the reaction tube with the first and second treatment gases at third and fourth flow rates, respectively, thereby forming second layer on the first layer, the second layer containing the impurity of a second density sufficiently higher than the first density; supplying the reaction tube with the first and second treatment gases at fifth and sixth flow rates, respectively, thereby forming third layer on the second layer, the third layer containing the impurity of a third density sufficiently lower than the second density; and diffusing the impurity contained in the second layer into the first and third layers by heating the first through third layers, thereby making an integral film of uniform impurity density from the first through third layers.

Claim 12

A method of forming a semiconductor film on a substrate, comprising the steps of: preparing a first treatment gas, the first treatment gas providing a main material of the semiconductor film as a result of thermal decomposition; preparing a second treatment gas, the second treatment gas providing an impurity, with which the semiconductor film is doped, as a result of thermal decomposition; heating a reaction tube; loading the substrate into the reaction tube; reducing pressure in the reaction tube; supplying the reaction tube with the first and second treatment gases at first and second flow rates, respectively, thereby forming first layer on the substrate, the first layer containing the impurity of a first density; supplying the reaction tube with the first and second treatment gases at third and fourth flow rates, respectively, thereby forming second layer on the first layer, the second layer containing the impurity of a second density sufficiently higher than the first density; supplying the reaction tube with the first and second treatment gases at fifth and sixth flow rates, respectively, thereby forming third layer on the second layer, the third layer containing the impurity of a third density sufficiently lower than the second density; and diffusing the impurity contained in the second layer into the first and third layers by heating the first through third layers, thereby making an integral film of uniform impurity density from the first through third layers.