A multi column lithography system for low and medium volume mask manufacturing
Viacheslav V. Kazmiruk, Ilya G. Kurganov, Alexander A. Podkopaev, Tatiana N. Savitskaja
In the paper is presented multicolumn e-beam lithography (MCL) system intended generally for production of templates.
The system was designed in two versions: with Schottky emitter and LaB6/CeB6 emitter.
System with Schottky emitter can be used for both mask making down to 7 nm HP node and for direct writing for 22 nm HP node. The system with LaB6/CeB6 cathode is for mask manufacturing with technology 45 nm HP node.
System consists of four small size columns with diameter about 70 mm. Accelerating voltage is 50 kV. Operating total beam current for the first system can be as high as 2 μA, for the second one – 1.2 μA. Writing speed on PMMA resist with sensitivity 100 μC/cm2 – 0.02 cm2/sec and 0.012 cm2/sec. Throughput is between 0.5 ÷ 1 mask per hour.
In the paper also there is a comparison of MCL and VSB (variable shaped beam) systems.
