| 摘要 |
<p>Methods and apparatus for high voltage, high current, fast acting, high temperature, high repetition rate synthetic diamond electrical switch and an improved particle and radiation detector are disclosed. Energy absorbed from incident electrons, ultraviolet photons or other radiation sources including soft and hard x-rays, gamma rays, alpha particles, other types of ions, neutrons or other sub-atomic particles is used to decrease the resistance of a synthetic (CVD) diamond membrane from its normal, high resistance 'off' state to a temporary, low resistance 'on' state. The controlled variation of the resistance of the diamond allows the membrane, when connected to an external circuit, to act as a repetitively pulsed electrical switch. Without the particle or radiation energy input, the membrane exhibits its normal very high resistance (for example, greater than 1012 Φ) and is in the 'off' state with negligible current. With particle or radiation energy input, the resistance plunges to low values (for example, much less than 1 Φ) and the current increases. The superior electrical field strength and thermal conductivity of both natural and synthetic diamond relative to doped silicon semi-conductors allow diamond membranes to hold off higher voltage and operate at higher temperatures than silicon semi-conductor junctions of comparable size. Practical limits to silicon or silicon carbide semi-conductor switches are less than 6 kV voltage hold-off in a single switch that can switch current densities of about 100 A/cm2 with approximately 1 νs turn-on and turn-off times. Silicon switches are unidirectional and limited to less than 400 °K operation (with respect to operating temperature).</p> |
