One embodiment pertains to an apparatus for reflection electron beam lithography, including at least illumination electron-optics, an electron-reflective pattern generator, projection electron-optics, a moving stage holding a target substrate, control circuitry, and a deflection system. A protrusion is formed on a back surface near the innermost part of an opening in a housing cover. Column select lines, orthogonal to IO lines and disposed in the third layer of metallic traces, except in the vicinity of IO lines, are provided in a linear configuration and shielded from parallel digit lines in the first layer of traces by traces of the intervening second layer of traces. The supporting plates can pivot up and down, and are biased by torsion springs to hold a water-supplying bottle between them in an inverted vertical position, which is connected to a valve of the humidifier, so that the bottle can’t tilt or shake to cause damage to the valve.