Table 3.

Plasma and wet etching of polyimide

Author	Etchant	Etching rate (μm/min)	Aspect ratio	Sidewall angle (deg)
Dry etching
Murakami et al. 105.	O2	4	15
.Fusao et al. 106,107	O2 + N2	>5	>10
Bliznetsov et al. 108.	O2 + CF4	3.5		Almost vertical
Zawierta et al. 109.	O2 + CF4 + N2	0.86		8
Wet etching
Lin et al. 184.	KOH + C2H7ON	16
Han et al. 119.	TPE3000	5	<1	30
Lena et al. 121.	NaOCl	≈0.2	138
Zuzanna et al. 120.	NaOCl	0.05	5.2	15
Kristina et al. 122.	NaOCl	0.35	≈6