Semiconductor processing techniques will be utilized to fabricate electron optical structures. In addition to electron microscopy the results of this research can also be applied to high definition cathode ray tubes (HDCRT), 10um period wigglers, and vacuum microelectronics. The areas considered in this proposal are: . A specimen holder with a binary selection of square apertures in a diaphragm ranging from 1um to 32um on a side, to support ultrathin specimens. . Miniature thermionic electron sources that have a flat emitting surface of varying size. There will be up to 10,000 of these filaments on each substrate. In addition a pseudo- blackbody source of electrons will be fabricated, this will have the advantage of a reduced evaporation of work function lowering impurities for tungsten. . Programmable thermionic electron sources that can control the emitting surface by changing the current path. This feature will add flexibility to the traditional triode design that relies on a Wehnelt electrode to control the emitting area. Electron specimen holders, and sources have been traditionally made with a beaker or in a machine shop. Semiconductor processing techniques developed for integrated circuit manufacture can generate 1-100um patterns in two and three dimensions with appropriate etching. This unprecedented control can be used to greatly improve the ease of manufacture of electron optical components and the resolution in microscopy.
