Silicon-on-insulator substrates: status and prognosis

The task in SOI substrate material is now to establish that high performance and reliability can be obtained routinely and consistently, in spite of the fact that SOI wafers are still made in a small batch processes. Circuits of interest must be obtained with high yield using SOI wafers which are acceptably low in cost and available in sufficient quantity on a timely basis, just as bulk Si wafers became identical and reliable enough that only spot check characterization needed to be done, SOI wafers have to strive for the same routineness to be of greatest interest to semiconductor manufacturers. While much progress in this direction has been made, much is still left to do. One of the difficulties facing semiconductor manufacturers is the wide variety of choices in available SOI material at a time when the goal is to narrow down the choices to an optimum one or two. Mainstream CMOS efforts have focused on two major options-SIMOX and BSOI, but even within these options there are potential variables.