Comparative study of AZPF514 and UVIII chemically amplified resists for electron beam nanolithography

Two commercial positive tone chemically amplified resists, AZPF514 and UVII I, were investigated and compared for their performance in e-beam direct wr ite of wafers at sub-150nm resolutions. The resist sensitivity, process lat itude and post exposure delay effect were studied. Both resists are of high sensitivity. They are insensitive to variation of post exposure bake condi tions. The post exposure vacuum delay effect is much more pronounced in AZP F514. AZPF514 also suffers severely the "T-topping" effect. Feature dimensi on below 150nm cannot be achieved with AZPF514, while sub-50nm lines have b een obtained with UVIII.