Fig. 3
From: Effect of C2H2F4/CF4O with low global warming potentials on SiNx etching as a CHF3 replacement
SEM images of 50nm depth partial SiNx etch with (a) CHF3 (110 sccm), (b) C2H2F4 (110 sccm), and (c) C2H2F4(80 sccm)+CF4O (30 sccm). SEM images for 200nm depth SiNx full etching with (d) CHF3, (e) C2H2F4, and (f) C2H2F4+CF4O. The other process conditions are the same as those in Fig 2.
