Second harmonic generation from Si/SiO/sub 2/: spectral and symmetry characteristics

Summary form only given. Second harmonic generation (SHG) only occurs, in the dipole approximation, in material that is noninversion symmetric. Consequently, in material with bulk inversion symmetry, SHG only occurs near a surface or an interface that breaks the inversion symmetry. Substantial interest has been paid to SHG from the Si(100)-SiO/sub 2/ interface because of its importance to the semiconductor industry. Results showing that SHG is sensitive to roughness at this interface have only furthered interest. Roughness is becoming critical as MOSFET gate oxide thickness shrinks to nanometer scale with shrinking gate dimension.