Title :
Plasma-induced charging reduction through ion-ion synchronous bias
Author :
Kanakasabapathy, Sivananda K. ; Overzet, Lawrence J. ; Cheung, Kin P. ; Malyshev, M.V.
Author_Institution :
Erik Jonsson Sch. of Eng. & Comput. Sci., Texas Univ., Dallas, TX, USA
Abstract :
Relatively electron-free, positive and negative ion (ion-ion) plasmas have been achieved in the afterglow of pulsed-power Cl2 ICP discharges. We obtain alternating bombardment by positive (Cl 2+) and negative (Cl-) ions, by applying a low frequency RF bias that has a modulation envelope phase-locked to the source power modulation and exclusive to the ion-ion plasma (synchronous bias). Such a bias was found superior to a continuous bias in negative ion extraction. Specially fabricated sensors were used to measure the aspect-ratio dependent wafer charge-up and show reduced charge-up with synchronous bias
Keywords :
chlorine; integrated circuit measurement; integrated circuit reliability; plasma materials processing; plasma radiofrequency heating; pulse modulation; surface charging; surface treatment; Cl2; afterglow; alternating bombardment; aspect-ratio dependent wafer charge-up; electron-free positive/negative ion plasmas; ion-ion plasma; ion-ion plasmas; ion-ion synchronous bias; low frequency RF bias; negative ion extraction; negative ions; phase locked modulation envelope; plasma-induced charging reduction; positive ions; pulsed-power Cl2 ICP discharges; sensors; source power modulation; synchronous bias; Capacitors; Electrons; Inductors; Phase modulation; Plasma accelerators; Plasma applications; Plasma sheaths; Plasma simulation; Plasma sources; Plasma temperature;
Conference_Titel :
Plasma- and Process-Induced Damage, 2001 6th International Symposium on
Conference_Location :
Monterey, CA
Print_ISBN :
0-9651577-5-X
DOI :
10.1109/PPID.2001.929980
