公开(公告)号：DE102005047105B3

公开(公告)日：2007-02-08

申请号：DE102005047105

申请日：2005-09-30

Applicant: INFINEON TECHNOLOGIES AG

Inventor： SCHMIDT GERHARD ,  SCHIFFER THORSTEN T ,  TRATTER EDGAR

IPC: H01L21/66 ,  G01N21/21 ,  H01L23/29

Abstract: Determining the dopant content of a doped amorphous semiconductor layer (10) on a carrier (1) comprises preparing a reference Tauc curve relating dopant concentration to the slope (b) of the linear region. The square root of the product of absorption coefficient (alpha ) and photon energy (E) (y axis) is plotted against photon energy and the slope (b) equals delta y/delta (E -Et) where Et is the band gap. The plot is repeated for the dopant layer to be tested using spectral ellipsometry, the slope (b) is found and thus the dopant concentration.