Resistance Of High Voltage And Ultra-fast Photoconductive Semiconductor Switches

Photoconductive semiconductor switch (PCSS's) is a kind of hybrid device which comprises photoconductive semiconductors and ultra-fast lasers. The first PCSS came out in 1975 in American. From then on with the progress of fs laser and semiconductor materials and process technonlgy the unique advantages over conventional power switches such as ultra-fast response (current rise/fall time at ps), ultra-high power impulse (MW), small jitters, GHz repetition rate were known and more and more attention were paid on the applications- in the UWB, THz generator, high power electromagnetic impulse etc.In the first part of this paper the basic theories and operation principles were introduced. Then the physics of the working of PCSS and parameters were given out. At last author gave out the standard principle for distinguishing the different types of PCSS. In the second part of this paper the each step for preparation PCSS were described in detail. Many process plans were designed for trying fabricating PCSS with semi-insulate semiconductor material GaAs/InP. Finally InP PCSS was made successfully.Testing the performance of the PCSS is also an important work in this paper. Different experiment projects were organized for observating several key capabilities: including test for anode/cathode contact film resistivity, breakdown voltage, research for the relationship between out impulse with the power of trigger laser and bias voltage, for the influence of laser trigger position to the performance of output impulse. The result of experiments means a lot in the PCSS application field.From the tests we got the block state breakdown voltage is bigger than 10000V, the maximum bias voltage under the 1kHz operation is no less than 9000V. The rise of trigger energy increased the output impulse voltage but when the energy get over a certain value this trend slowed down and the export voltage go to a fixed value. Different laser trigger positions influenced the output impulse a lot which increased with the trigger point moving from the cathode to the anode. The output got its peak value when the laser near the anode but that decreased when the trigger at the edge of anode.The results were analyzed, and explanations based on theory of semiconductor and the inside electronic distribution were given. These conclusions made sense in the future research for the operation physics states and the non-linear mode.