公开(公告)号：JPH07201807A

公开(公告)日：1995-08-04

申请号：JP31290294

申请日：1994-12-16

Applicant: IBM

Inventor： SUCHIIBUN JIYOOJI BAABII ,  TONII FUREDERITSUKU HAINTSU ,  ARURITSUCHI HOFUAA ,  REPINGU RII ,  BIKUTAA JIYOSEFU SHIRUBESUTORI

IPC: G01B11/06 ,  G01N21/00 ,  G01N21/45 ,  H01L21/302 ,  H01L21/306 ,  H01L21/3065

Abstract: PURPOSE: To monitor an etching end point of a thin film on the surface of a wafer to be etched in real time on the spot by normalizing a secondary higher- harmonic component in real time and responding to a 1st and a 2nd output signal. CONSTITUTION: A sending-out means sends a 1st beam 52 to a border surface 12 between a film 10 and a substrate 20 at a specific angle of incidence. The 1st beam 52 is reflected by the border surface 12 to generate a 2nd beam 62. The 2nd beam 62 includes secondary higher-harmonic component generated as the primary higher-harmonic component of the 1st beam 52. The secondary higher-harmonic components are generated by the reflection of the 1st beam 52 at the border surface 12. A normalizing means which responds to the 1st and 2nd output signals normalizes the sent-out secondary higher-harmonic component of the 1st beam 52 to generate a 3rd output signal, representing the generation of specific variation of the normalized sent-out secondary higher-harmonic component, and the specific vibration corresponds to the etching end point of the film 10 on the substrate 20. Namely, realtime field end point detection can be performed.