Turnover phenomenon of N NN plate contact Si device and second breakdown in the transistor

The dependence of turnover characteristics IM, VM, TMand EMof N⁺N N⁺plate contact Si device upon the applied condition was investigated. The dimensions of the device were: N-layer thickness ≃ 210µ, N⁺layer thickness ≃ 20µ, diameter mmΦ, and Pb solder-layer thickness = 250 ∼ 300µ. The N layer has the resistivity of four groups, ranging from 3 to 220 ohm-cm. Applied voltage has a waveform with a linearly rising part and an adjoining flat part. When the applied voltage is increased, IMincreases. whereas TM, and EMdecrease. We designate this effect the varying characteristics. When the applied voltage is higher, IM, TM, and EMsaturate and reach the saturated values of IMS, TMS, and EMS. In this case the applied voltage has a constant value of the slope. The saturated characteristics of IMS, TMS, and EMSwere also studied by varying the slope of the applied voltage. The significance of turnover phenomenon in the device consists in the resemblance to second breakdown (SB) in the transistor as shown in the previous report. The report showed that SB characteristics varied considerably with the applied conditions and were characterized by the varying and saturated effects. This may indicate that SB is not a peculiar phenomenon to the transistor, but is also applicable to the semiconductor itself.