Title :
Reduction of charging damage of gate oxide by time modulation bias method
Author :
Ono, Tetsuo ; Oomoto, Yutaka ; Mizutani, Tatsumi ; Yoshioka, Ken ; Ogawa, Yoshibumi ; Kofuji, Naoyuki ; Izawa, Masaru ; Goto, Yasuo ; Kure, Tokuo
Author_Institution :
Hitachi Ltd., Yamaguchi, Japan
Abstract :
The charging damage of gate oxide films caused during plasma etching is reduced by the time modulation (TM) bias method. The radio frequency (RF) bias applied to the substrate is pulse modulated to control the energy and the quantity of accelerated ions. The charging potential of line patterns caused by the electron shading effect decreases during off periods of RF bias. In addition, the emission intensity signal of the optical endpoint monitor indicates suppression of reactive ion etching (RIE) lag. These factors result in the reduction of charging damage
Keywords :
dielectric thin films; integrated circuit reliability; integrated circuit testing; integrated circuit yield; plasma materials processing; pulse time modulation; sputter etching; RF substrate bias; RIE lag suppression; SiO2-Si; TM bias method; accelerated ions; charging damage; charging damage reduction; electron shading effect; emission intensity signal; gate oxide; gate oxide films; line pattern charging potential; line patterns; optical endpoint monitor; plasma etching; pulse modulation; radio frequency bias; reactive ion etching lag suppression; time modulation bias method; Acceleration; Electron optics; Etching; Optical pulses; Particle beam optics; Plasma accelerators; Plasma applications; Pulse modulation; Radio control; Radio frequency;
Conference_Titel :
Plasma Process-Induced Damage, 1999 4th International Symposium on
Conference_Location :
Monterey, CA
Print_ISBN :
0-9651577-3-3
DOI :
10.1109/PPID.1999.798840
