公开(公告)号：JPH07193057A

公开(公告)日：1995-07-28

申请号：JP29419994

申请日：1994-11-29

Applicant: ADVANCED MICRO DEVICES INC

Inventor： SABUHATSUSHIYU GUPUTA ,  SUUZAN CHIEN ,  ANJIERA HIYUI

IPC: C23F4/00 ,  H01L21/28 ,  H01L21/302 ,  H01L21/3065 ,  H01L21/311 ,  H01L21/3213 ,  H01L21/768 ,  H01L23/522

Abstract: PURPOSE: To enable via holes and openings with high aspect ratio to be formed in SiOx without deeply etching by using high pressure CHF3 and N2 , and high flow rate He plasma. CONSTITUTION: A lower electrode 21 of Al is supported by a plasma reaction apparatus housing 23, and a wafer 24 is clamped on the electrode 21 by a clamp 22. The electrodes 20 and 21 are positioned with a gap narrower than 1.5 cm, reactive gas flow containing CHF3 and N2 , is put into a sealed region, and RF power P with frequency of the order of 400 kHz is applied to the electrodes. Further, the plasma is cooled by inelastic collision, which causes high flow rate of He gas with low mass to mix with the reaction gas. However, the flow rate of He gas is greater than 96% of the whole mass flow. The wafer is processed by cooling He gas in the back face of the wafer which is performed under pressure via a duct 26 which passes He gas through a control device 25 to a space 30 below the wafer 24.