Imaging capability of low-energy electron-beam proximity-projection lithography toward the 65/45-nm node

Abstract

Imaging capabilities of low-energy electron-beam proximity-projection lithography (LEEPL) are discussed focusing mainly on the hole patterns for chemically amplified resist. LEEPL needs a multi-layer process with a resist layer less than 100 nm thick. To achieve the imaging performance of the 65nm node (80nm), we optimized intermediate spin-on-glass (SOG) layer and top-layer resists, which were selected carefully. 80 nm hole patterns were achieved with 10% exposure latitude, and current imaging position and 45 nm node positions were investigated using σ QBP. σ QBP was improved from 64.5 nm to 48.9 nm.

Electron beam nanolithography and testing: ways of increasing the resolution and the throughput

“…The system has the resolution 65 nm, exposure field of 46х46 mm, and allows exposure up to 50 wafers of diameter 200 mm or 40 wafers 300 mm in diameter per an hour respectively. By optimization of thickness of resist layers, the resolution better than 50 nm was achieved on this tool 18 . The optical resolution d in systems of that type is defined by a gap width of h between a mask and a wafer and convergence angle of a beam: d = αh.…”