Influences of etcher chamber condition on critical-dimension shifts in advanced floating gate etching process

The authors investigated the correlation between variation of post-etch critical dimension (ECD) and etcher chamber condition during floating gate etching process. This paper presents the significantly effective method of utilizing the SF 6 /O 2 -based very long plasma-chamber cleaning or the novel Transformer coupled plasma (TCP) window temperature design not only achieves a stable gate CD (CD variation