NANOBEAM PROCESS SYSTEM - AN ULTRAHIGH-VACUUM ELECTRON-BEAM LITHOGRAPHY SYSTEM WITH 3 NM PROBE SIZE

We have constructed a ''nanobeam process system'' which is applicable to high resolution electron beam lithography using inorganic resists a nd is also compatible with electron beam induced surface reaction. It is a 50 kV electron beam Lithography system with a gas introducible ul trahigh vacuum sample chamber using a double chamber stage system whic h isolates stage mechanisms from the sample chamber. The probe size me asured with a knife edge method was 2.8 nm, where the probe current wa s 127 pA. The base pressure of the sample chamber was 3.5X10(-7) Pa af ter baking. The pressure of the gun chamber did not vary at all and th e pressure rise of the mechanism chamber was 3X10(-6) Pa when the pres sure of the sample chamber increased to 1X10(-3) Pa during N-2 gas int roduction. Standard deviations of stitching and overlay accuracy were 14 and 18 nm, respectively. Line patterns with a width of about 5 nm a nd a pitch of 15 nm were delineated in SiO2 when used as a high resolu tion resist. (C) 1995 American Vacuum Society.