Method for fabricating a substrate with useful layer on high resistivity support
View Patent ↗A substrate suitable for producing a high frequency electronic circuit. This substrate includes a support substrate having a controlled amount of interstitial oxygen and which is treated to precipitate at least some of the oxygen therein; and a useful layer supported by the support substrate. Advantageously, the support substrate has high resistivity and includes oxygen precipitates beneath the useful layer while also being free of depleted zones of oxygen precipitates adjacent the useful layer. This is prepared by the methods disclosed herein which are applicable in particular to SOI substrates.
1. A substrate suitable for producing a high frequency electronic circuit, the substrate comprising: a support substrate that has a surface and includes a controlled amount of interstitial oxygen and is treated to precipitate at least some of the oxygen therein; and a useful layer supported by and in contact with the support substrate; wherein the support substrate has high resistivity and includes oxygen precipitates beneath the useful layer and treated to be free of depleted zones of oxygen precipitates adjacent the surface of the support substrate at the interface with the useful layer.
2. The substrate of claim 1 , wherein the support substrate is a semiconductor of the SOI-type.
3. The substrate of claim 1 , wherein the support substrate has a concentration of interstitial oxygen that is approximately 15×10 17 /cc or higher prior to oxygen precipitation.
4. The substrate of claim 1 , wherein the useful layer comprises a material selected from the group consisting of silicon, silicon-germanium, gallium arsenide, indium phosphide, silicon carbide and gallium nitride.
5. The substrate of claim 1 , wherein a portion of the useful layer comprises an insulating layer, wherein the insulating layer is in contact with the support layer at the interface.
6. The substrate of claim 1 , wherein a portion of the support substrate comprises an insulating layer which is in contact with the useful layer at the interface.