DEPENDENCY OF ADHESION BEHAVIOR ON THERMAL-STRESS DISTRIBUTION IN PHOTORESIST MICROPATTERNS

We report an excellent correlation between adhesive behavior in HF aqueous solution and internal distribution of thermal stress in a photoresist pattern. The stress distribution was analyzed using the two-dimensional finite element modeling in the cross section of the photoresist pattern. The large envelope shape, which indicates weak adhesion, was confirmed by the concentration of stress at the resist-substrate interface. In particular, the hardened layer of the photoresist pattern surface has the effect of forming the two-step shape of the etching envelope due to isotropic and lateral intrusion.