SOI wafers with MEMS structures and backfilled isolation trenches defined cross-section

the design of filled isolation trenches, in particular the transition regions in silicon-free areas (z. B. mines), it is stated in the realization of MEMS structures on SOI wafers, whereby a safe dielectric isolation of neighboring silicon regions is ensured. The isolation is achieved by isolation trenches backfilled. In this case, it is important that the etched silicon from the surrounding ends of the grave filling in the pit with the active sensor structure are free of conductive, non-completely removed silicon strip. This is achieved by undercut walls of the isolation trenches. In addition, the grave backfill should be such that they can be easily removed again in the transition area. The technological implementation requires no special additional operations.