Silicon-silicon dioxide interface of predetermined space charge polarity
Abstract
Abstract In the fabrication of a semiconductor device having a siliconsilicon dioxide interface, the polarity of the space charge region associated with the interface is predetermined by a method which begins with the step of pretreating the silicon surface with a selected reagent capable of inducing the desired space charge polarity. For example, a pretreatment with chromic acid induces a negative space charge region, whereas a pretreatment with nitric acid induces a positive charge. The interface is then formed by vapor deposition of a silicon dioxide layer on the silicon surface. The pretreatment has been found capable of inducing a predetermined charge when the interface is provided by vapor deposition, but is wholly ineffective when the interface is provided by thermal oxidation. It is well known that thermal oxidation of a silicon surface inherently produces an interface having a positive space charge region.
Inventors
- 👤 Frank J Barone
- 👤 Donald L Tolliver
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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