Ming-jian SUN, Cheng-yuan DONG, Shi-shiung LIN. Dry etching for the planarization layer of thin film transistors[J]. Chinese journal of liquid crystals and displays, 2019, 34(11): 1055-1060.
DOI:
Ming-jian SUN, Cheng-yuan DONG, Shi-shiung LIN. Dry etching for the planarization layer of thin film transistors[J]. Chinese journal of liquid crystals and displays, 2019, 34(11): 1055-1060. DOI: 10.3788/YJYXS20193411.1055.
Dry etching for the planarization layer of thin film transistors
In order to reduce the parasitic capacitances of thin film transistor (TFTs)
a new type of planarization material was adopt. However
neither reactive ion etching (RIE) nor enhanced capacitive couple plasma (ECCP) could well etch this film. Accordingly
the combination of RIE and ECCP was proposed to improve the etching effects. When the thickness of planarization layer was 2.0
μ
m
we first etched 1.5
μ
m of the planarization layer by RIE mode (7 kW/20 Pa)
then etched the rest as well as the underneath silicon nitride film by ECCP mode (5 kW+4 kW/8 Pa); the surface of via hole was smooth without undercut issue
and the via hole critical dimension (CD) was 6.12
μ
m. These results lay a solid foundation for the design and fabrication of the high-resolution and low-power products with this new planarization layers.
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