Both electron beams and ion beams have unlimited resolution as far as semiconductor manufacturing is concerned. Both have serious throughput limitations because of the difficulties of engineering suitable masks and because of space charge (particle-particle repulsion) effects. Masks are a problem first because of the difficulties of generating a pattern with better than 10 nm tolerance on short range (<lmm) edge placement precision and with freedom from defects, and of providing a pellicle to maintain a defect-free mask pattern. As a result a variety of maskless configurations are now being researched. Space-charge is regarded as more serious for ion beams than for electrons because of the lower elm ratio for ions but this is offset by the higher sensitivity of resists to ion exposure. It is not yet clear whether space charge effects can be effectively mitigated in any practical system employing only one optical axis. Space charge effects can be avoided through the use of multiple optical axes but now the challenge is to combine the individual fields associated with each axis into one large coherent field. One approach is to use an array of miniature columns, another is to employ an integrated array of micromachined proximal probes (e.g. AFM tips) that field emit electrons into thin resist. A third approach is to use a micromachined integrated structure containing an array of optical axes with uniform focusing fields across the array.