Somewhere between the cathode-ray tubes (CRTs) so common in electronic displays and the solid-state circuits that drive them lies the technology of vacuum microelectronics. Here arrays of extremely small charged-particle emitters are housed in thin vacuum chambers to perform many electronic functions. Central to these devices are tiny cone-shaped cathodes, so sharp that the energy required to emit electrons from their tips is very small and the emitting process is called field or cold cathode emission. This technology was invented at SRI over 40 years ago, and the world has no better expert or practitioner in this field than Capp Spindt. In fact, these small emitters are known everywhere as "Spindt cathodes."
Spindt joined SRI in 1959 and in 1966, he invented and developed processes for microfabricating gated arrays of field-emission cathode tips. These very efficient, cold cathodes have been the enabling technology for a new technical field dedicated to applying microfabrication techniques to vacuum devices and for a rekindled interest in vacuum devices within the scientific community. Spindt cathodes are used for flat-panel displays of incredible brightness, in microwave amplifiers, in electron-beam etching in the building of integrated circuits, and for many space applications. Spindt also championed the efforts to develop microfabricated field ionization sources, which have been used as the ionization source for nonfragmenting mass spectrometry of large molecular-weight compounds and can be used in diverse applications ranging from spacecraft propulsion to biomedical analytic instrumentation.
As the world discovered the Spindt cathode’s utility, Spindt helped found the ongoing worldwide conferences on vacuum microelectronics that this year will see its 17th annual meeting. He contributes to world understanding of vacuum micro- electronics by many positions on committees and editorial boards as well as by delivering invited lectures all over the world. In 1990, he received his Ph.D. and in 1992, he was honored as an SRI Fellow. In 1996, the Society for Information Displays awarded Spindt the Jan Rajchman Prize for inventing and developing field-emission flat-panel displays using micro-tip structures.
Capp Spindt’s legacy to SRI is this broadly useful technology -- the subject of active SRI projects -- as well as his continuing contribution to world understanding of vacuum microelectronics.