EB Direct Writing Technology for Micron and Sub-Micron Structure

At present, there are two ways of developing EB direct writing technologies. One is the application of VLSI fabrication such as the 512 KbitROM, which has been developed in this group (1) and 256 Kbit RAN developed in NTT in Japan (2). The other is the application to custom LSI fabrication, such as QTAT in IBM (3) and mask ROMs with contact hole formation (4). In this paper, EB direct writing technology for micron MOS process applications to VLSI fabrication is described. Then, submicron EB lithography will be discussed to show the course of EB direct writing technology advancement.