The relationships of contact angle among different substrates, the role of dehydrating bake on photoresist profile and the relationship between contact angle and photoresist profile are addressed in this paper. Generally speaking, when the HMDS priming time increases, the contact angle of all the substrates increases no matter what the adhesion priming temperature and dehydrating bake time/temperature used. Among these substrates, tungsten silicide always has the largest contact angle and its minimum acceptable priming time is about 5 seconds. Regarding the priming temperature, largest contact angle is obtained with priming temperature around 50$DGR@C for doped poly, bare silicon, and tungsten silicide substrates, while for Teos substrates there is no significance difference on priming temperature as it's beyond larger than 30$DGR@C. In terms of dehydration temperature, lower baking temperature results in larger contact angle. However, as far as the photoresist profile is concerned, higher contact angle does not guarantee that profile is vertical without undercut or tailing problems. In view of improving the photoresist profile, the dehydrating bake is unavoidable and the temperature should be around 100$DGR@C.
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