| 摘要 |
PURPOSE:To make it possible to widen the range of control of impurity density by a method wherein the impurity raw material, which controls the conductivity of a semiconductor thin film, is intermittently introduced in pulse-like from into the surface of a compound semiconductor thin film while an eptaxial growing operation is being performed. CONSTITUTION:Impurity raw material, with which the conductivity of a semiconductor thin film is controlled, is intermittently introduced in pulse form into the surface of a compound semiconductor thin film while a compound semiconductor thin film is being epitaxially grown. Accordingly, the range of control of dopant density in a thin film can be changed by altering the ratio of the time during which the impurity raw material is introduced and the time during which the impurity raw material is not introduced, in other words, by changing the duty ratio of introduction. As a result, the range of control can be widened by several figures or more by changing the duty ratio.
|
