AN UNDERCUT FREE 1 MICRO THICK AZ-5200 POSITIVE E-BEAM RESIST PROCESS FOR HIGH CURRENT DENSITY APPLICATIONS
Original Publication Date: 1988-Oct-01
Included in the Prior Art Database: 2001-Oct-29
AZ-5200 positive resist is found to have a sensitivity (20 microcoullcm') and a contrast (gamma=3) which make it very attractive fore-beam lithography. Unfortunately, when coated in a thickness of 1.0 micro or greater, this and other novalac based e-beam resists exhibit severe undercutting if exposed with a high current density instrument and slightly overdeveloped (see Fig. 1). Until this problem was solved, AEBLE-150 e-beam lithography was unacceptable for a P-tub implant layer of a CMOS device and for some ASIC applications.