WET SILYLATION AND DRY DEVELOPMENT WITH THE AZ-5214(TM) PHOTORESIST

A positive tone surface imaging process using wet silylation and dry development of AZ 5214(TM) photoresist was developed. The process steps are spinning and prebake of the photoresist, i-line exposure, postexposure bake, wet silylation, and dry development in O2 plasma. The process has been developed using statistically designed experiments, starting with a Placket-Burman screening experimental design for six variables. These experiments showed that the composition of the silylating solution was the most important variable. As a result, a mixture experimental design followed, with the concentrations of the silylating agent and solvents as the only variables. Characterization of the process and process window definition were done with ultraviolet spectroscopy of films made on quartz wafers, and scanning electron microscope photographs.