Effect of implant dose on formation of buried-oxide Si islands in low-dose SIMOX

There are still important issues that remain on the microstructure of low-dose SIMOX that may affect its quality and performance as an SOI material. These issues include the presence of crystalline defects in the top Si layer and the presence of Si islands in the buried oxide (BOX) which can severely degrade dielectric properties. While the reasons for crystalline defect formation have been recently determined, the mechanism(s) of Si island formation in the BOX are still unclear. Such understanding could assist in improved processing for fabricating high quality BOX layers in low-dose SIMOX. In this paper we report on the effect of implant dose on the microstructural changes found during Si island formation.