Using surface processing technology

AZ5214 E photoresist lithography and inverted

magnetron sputtering Ni Cr alloy

stripping out metal pier with height of 2. 3 μm

fill polyimide as sacrificial layer

and then on sacrificial layer photolithography

depositing metal to form metal bridge

in the center of metal bridge surface

embed the second Bragg reflector. Using O2 plasma etch and remove polyimide film

form cavity structure

without silicon bonding

overcome shortcoming that height is not high enough and the limited tuning range of traditional FP cavity

bad flatness of cavity and low demand of equipment

and it can make a large array structure

easy to integrate with the detector. Focus on key fabrication process that is Ni Cr metal stripping process

propose solutions based on existing technical defects.