Super Junction LDMOS Transistors - Implementing super junction LDMOS transistors to overcome substrate depletion effects

摘要

The super junction (SJ) concept (Coe et al.) applied to power semiconductor devices is attractive due to its potential for reducing on-resistance at a given breakdown voltage. Discrete SJ vertical power devices have recently become available commercially. However, lateral SJ devices have not materialized for several years partly due to the fact that the lateral SJ structure, implemented on silicon substrates, suffers from substrate-assisted depletion effects which reduce the breakdown voltage. This article discusses the various device structures that have been proposed to eliminate the substrate-assisted depletion effects in SJ-lateral double diffused MOS LDMOS transistors (SJ-LDMOSTs). The concept of the SJ device and vertical and lateral SJ structure was summarized. The substrate-assisted depletion effects are described in detail. The alternative implementations proposed to suppress the substrate effects were then discussed. And the experimental implementation results are summarized and discussed to identify the most likely option for the implementation of lateral SJ-LDMOSTs