Determining boron concentration profiles in semiconductors by nuclear method

The 10B(n,α)7Li nuclear reaction was used for determining boron concentration profiles. The WWR-S reactor was used as a neutron source. The charged products of the nuclear reaction (7Li, 4He) formed upon impinging of a slow neutron beam having a flux of 1.6x108 cm-2s-1 on a target placed in a vacuum chamber were recorded using a semiconductor detector. The energy spectra of the reaction products were recorded by a 1024-channel amplitude analyzer and processed by an EC 1010 computer. The method described allows the nondestructive analysis of the boron content down to a depth of 2x10-6 m from the sample surface. Boron additions at a concentration of 2x1012 at/cm can be determined with an accuracy of up to 10%. (J.P.)