Patent ID: 7670857
Filing Date: 2010-03-02
Classification: G01N

Abstract:
1. An inspection method for inspecting an internal state of a silicon on insulator (SOI) wafer by measuring silicon islands within an insulating base material of a silicon oxide film formed in the SOI wafer, the method comprising: irradiating ions or electrons upon the surface of the inspection region of said silicon oxide film; imaging a surface image of secondary electrons emitted from said surface and from its vicinity; etching said inspection region; imaging a surface image successively with secondary electrons emitted from an underlying surface and from its vicinity, renewed successively at the etched depth; measuring said silicon islands within said silicon oxide film based upon accumulated said surface images; and inspecting the internal state of said SOI wafer, wherein said etching is performed with an ion-beam having an acceleration voltage of 15 to 40 keV, beam current greater than or equal to 3.6 pA, and beam diameter greater than or equal to 18 nm, and wherein said etching and said imaging of said surface image are performed at the same time.