| 摘要 |
1,086,704. Controlled rectifiers. COMPAGNIE GENERALE D'ELECTRICITE. Nov. 26, 1964 [Dec. 12, 1963; March 11, 1964], No. 48188/64. Heading H1K. In a PNPN or symmetrical PNPNP or NPNPN controlled rectifier at least one of the outermost layers is formed in two parts, one of which forms with the adjacent layer a junction with backward diode characteristics and the other of which forms a junction with normal diode characteristics. The tunnel junction is in the main current path and the triggering voltages are applied through an electrode attached to the conventional diode forming layer. The arrangement overcomes the disadvantage of high triggering current normally associated with PNPN devices using outer tunnel junctions. In a typical device of the PNPNP type both outer layers are formed in two parts side by side, the different junction characteristics resulting from a non-homogeneous doping of the adjacent inner layers. Alternatively the device may be constructed as shown in Fig. 3b, the two layers being formed in common and then separated by cutting a slot 5. In this case a large main electrode P3 is provided on one face to facilitate cooling, while the remaining electrodes are disposed on the other face. |
