FABRICATION OF HIGH-ASPECT-RATIO STRUCTURES FOR MICROCHANNEL PLATES

Substrates for microchannel plates have been fabricated using Si micro machining techniques. High aspect ratio pores are constructed using re active ion etching and streaming electron cyclotron resonance etching, and low-pressure chemical vapor deposition (LPCVD). In one process, 4 0 mu m deep pores with 2 mu m openings on 4 mu m centers are directly etched in Si. Alternatively, pores with aspect ratios of 30:1 are cons tructed in a low-stress SiNx membrane using a sacrificial template pro cess whereby pillars of Si are etched and then subsequently backfilled with a dielectric using LPCVD. (C) 1995 American Vacuum Society.