We present the results from a thorough investigation of the bond strength between the photo-polymer SU-8 and Au. The data were obtained by pull-test experiments, below the glass transition temperature of the polymer. The different aspects that we investigated were:(i)the effect of using different adhesion promotors between the SU-8 and Au; (ii) the influence of the processing sequence, keeping either Au or SU-8 as the bottom layer; (iii) the importance of the UV exposure dosage of the SU-8. For comparison, also the bond strength between SU-8 and other materials was measured. For SU-8 and Au without any adhesion promoter we find a bond strength of 4.8+/-1.2 MPa for a 7.5 micr.-layer of SU-8. The value of the bond strength can be increased additionally by up to 75% using an adhesion promoter and fully optimising the processing con- ditions of the SU-8.
|Publication status||Published - 2005|