CHEMICALLY AMPLIFIED AZPN114 ELECTRON-BEAM RESIST FOR ADVANCED PHOTOMASK FABRICATION

Electron beam resists having high sensitivity and high resistance to dry etching are of interest generally for sub-half micron device production and in particular for e-beam fabrication of 5 x masks and reticles. Novolac based chemically amplified AZPN114 resist has been characterised at 20 keV exposure using an EBMF 10.5 lithography system under a range of dose, post-exposure bake, development, wet chemical etch and plasma etch conditions. A low voltage SEM metrology scheme based on the linear approximation technique for linewidth measurement has been used to monitor the in-process CD variability. Linewidth deviation of + / - 0.03 mum for 1.5 mum line features has been achieved for a dose of < 5 muC/cm2. For high throughput mask production, 10 keV exposures have been explored. Preliminary experimental results suggest that a dose approximately 2 muC/cm2 is adequate without loss of CD controllability.