Patent ID: 9136113
Filing Date: 2015-09-15
Classification: H01L

Abstract:
1. A process for avoiding formation of an Si—SiO 2 —H 2 environment during a dissolution treatment of a semiconductor-on-insulator structure, which process comprises: providing a semiconductor-on-insulator structure successively comprising a carrier substrate, an oxide layer, a thin layer of semiconductor material and a peripheral ring in which the oxide layer is exposed, the thin layer of semiconductor having a thickness that is less than 500 nm, the thickness of the oxide layer being less than 100 nm; encapsulating at least the exposed oxide layer of the peripheral ring with semiconductor material by performing a creep thermal treatment; and performing an oxide dissolution treatment and dissolving at least a portion of the thickness of the oxide layer, the oxide dissolution treatment including subjecting the semiconductor-on-insulator structure to a temperature between 1050° C. and 1300° C. in a neutral or reducing atmosphere having an oxygen content lower than 10 ppm and avoiding formation of an Si—SiO wherein the thickness of the thin layer of semiconductor material of the semiconductor-on-insulator structure, prior to the oxide dissolution treatment, is at least twice the portion of the thickness of the oxide layer that is dissolved in the oxide dissolution treatment; and wherein the process further comprises forming a mask on the peripheral ring in which the oxide layer is exposed after the creep thermal treatment and prior to the oxide dissolution treatment, the mask covering the exposed oxide layer such that the oxide layer is not exposed to the atmosphere during the oxide dissolution treatment.