SILICON CONTROLLED RECTIFIERS: LATERAL TURN-ON VELOCITY, LATERAL FIELD DISTRIBUTION, AND LATERAL SKIP PHENOMENON
Abstract
The silicon controlled rectifier (SCR) is essentially an 'area' device whereas the transistor is a 'periphery' device. In the application of SCRs some trouble arises in making use of this large area because of the slow spreading of turn-on from the gate region. SCRs were specially constructed to permit the direct observation of the lateral spread of turn-on within the device. The effects on the spread of turn-on of load current, base widths, temperature, anode-cathode voltage, the gate signal, and a large inhomogeneity were observed. An analysis of a linear and of a cylindrical transistor with lateral currents in both the emitter and the base layers is included. The results are written in a general form and can be applied to many specific cases including those that have a lateral current only in the base layer or only in the emitter layer. A lateral current in an emitter layer of an SCR is shown to vary the lateral field in the base layers and also to change the distribution of the current density injected from the emitter to the base. A method of using lateral emitter layer currents in an SCR to increase the spreading velocity of the on-region and, at higher currents, to turn on quickly areas of the SCR remote from the gate contact is demonstrated experimentally.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1965
- Accession Number
- AD0464818
Entities
People
- William H. Dodson
Organizations
- Carnegie Institute of Technology