I have metal (In)/ WS2 connection. At 250 microA it is showing ohmic characteristics. If I apply higher or lower current it does not show any ohmic characteristics?
How can you determine the ohmic characteristics at only one current value. The current voltage characteristics should be linear for the whole range of current. I have not used WS2 but I use GaAs and make ohmic contacts on it. I apply current upto plus and minus 500mA and should see a linear I-V.
I believe your contact is not currently ohmic. you may want to check if you need to anneal your samples if haven’t done yet...