Effects of Plasma Treatment on Contact Resistance and Sheet Resistance of Graphene FET

Chang-Ho Ra, Min Sup Choi, Daeyeong Lee, Won Jong Yoo
2016 Journal of the Korean institute of surface engineering  
We investigated the effect of capacitively coupled Ar plasma treatment on contact resistance (R c ) and channel sheet resistance (R sh ) of graphene field effect transistors (FETs), by varying their channel length in the wide range from 200 nm to 50 μm which formed the transfer length method (TLM) patterns. When the Ar plasma treatment was performed on the long channel (10 ~ 50 μm) graphene FETs for 20 s, R c decreased from 2.4 to 1.15 kΩ·μm. It is understood that this improvement in R c is
more » ... ement in R c is attributed to the formation of sp 3 bonds and dangling bonds by the plasma. However, when the channel length of the FETs decreased down to 200 nm, the drain current (I d ) decreased upon the plasma treatment because of the significant increase of channel R sh which was attributed to the atomic structural disorder induced by the plasma across the transfer length at the edge of the channel region. This study suggests a practical guideline to reduce R c using various plasma treatments for the R c sensitive graphene and other 2D material devices, where R c is traded off with R sh .
doi:10.5695/jkise.2016.49.2.152 fatcat:vf4rsmnvtvaw3ijsrqufmu4jq4