Patent ID: 6217951
Filing Date: 2001-04-17
Classification: H01J,H01L

Abstract:
An impurity introduction method, comprising the steps of:holding, in a vacuum chamber, an impurity solid including impurity and a solid sample into which said impurity is introduced;introducing inert or reactive gas into said vacuum chamber to generate plasma composed of said inert or reactive gas;applying to said impurity solid a first voltage which allows said impurity solid to serve as a cathode for said plasma, performing sputtering of said impurity solid by ions in said plasma, and thereby mixing said impurity included in said impurity solid into said plasma; andapplying to said solid sample a second voltage allowing said solid sample to serve as a cathode for said plasma or a third voltage allowing said solid sample to serve as an anode for said plasma in an interchanging manner and introducing said impurity mixed into said plasma to a surface portion of said solid sample, wherein an introduction depth of said impurity introduced into said surface portion of said solid sample is controlled by controlling values of said second voltage and said third voltage, said second voltage and said third voltage being generated by separate sources.