| 摘要 |
<p>Irradiated regions are formed in materials such as semiconductor bodies by nuclear radiation where the irradiated regions are of a desired thickness, dosage and dosage gradient, a desired distance from a selected surface of the material. A nuclear radiation beam from a given radiation source radiating particles with molecular weight of at least one (1) is provided that can penetrate the material through a selected surface to a depth greater than the maximum depth of the irradiated region from the selected surface. A beam modifier is formed of a given material and non-uniform shape to modify the energy of the radiation beam on transmission therethrough to form a transmitted radiation beam capable of forming an irradiated region of a desired thickness and dosage gradient in the material a given distance from the selected surface on irradiation of the material through the selected surface with the transmitted radiation beam. The material in which the desired irradiated region is to be formed is positioned with the selected surface thereof to be exposed to the radiation beam from the radiation source on transmission through the beam modifier. The material is thereafter irradiated through the beam modifier and through the selected surface with the radiation beam, preferably while the beam modifier and material are moved relative to each other through a predetermined motion, to form in the material an irradiated region of desired thickness, dosage and dosage gradient, a desired distance from the selected surface. The irradiated region thus formed in semiconductor bodies are particularly of value in changing the electrical characteristics without substantial change of other electrical characteristics.</p> |
