Large area electron beam direct imaging technology for printed wiring boards

An electron beam direct imaging system that can image electric circuit patterns directly on printed wiring boards (PWBs) from computer-aided design (CAD) data without using film masks has been developed. The system realizes beam deflection over a large field of 100 mm×100 mm. The deflection field can be imaged in less than 1 s with an accuracy of better than ±30 μm. The maximum deflection speed is 254 m/s, and the beam diameter in full width at half maximum is 40 μm. This technology can use the same kinds of resists as those for conventional photolithography. It was shown that fine patterns with line widths less than 100 μm can be imaged for PWBs 340 mm×400 mm in size by stitching deflection fields