| 摘要 |
PURPOSE:To control surface-defect density generated in an element active region at a constant value by using the ratio of an absorption coefficient alpha1106 in a wave number of 1106cm<-1> resulting from interstitial oxygen in single crystal silicon to that in a wave number of 513cm<-1> resulting from substitutional type oxygen as a monitor for the generation of minute defects in an silicon semiconductor wafer. CONSTITUTION:When the absorption coefficients of infrared beams of 1106cm<-1> and 513cm<-1> before heat treatment are each represented by alpha1106 and alpha513 and relationship with internal minute-defect density to the k value = alpha1106/alpha513 of the absorption coefficients is taken, internal defect density extends over 2X10<8>cm<-3> or less in a sample having k<4.5, but surface dislocation density (a pattern-end dislocation generation rate) is also lowered when it is kept within the range. Accordingly, when an element formation process consists of a heat treatment process of 1,000 deg.C or less as seen in an nMOS having no well process, the generation of internal minute defects is inhibited by specifying the k value of an silicon wafer and holding k<4.5, thus preventing the generation of a surface dislocation.
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