A shallow trench isolation using nitric oxide (NO)-annealed wall oxide to suppress inverse narrow width effect

A simple method to suppress INWE of transistor based on STI technology has been demonstrated in this paper. In order to prevent the boron out-diffusion through the trench sidewall, the nitric oxide (NO)-annealed wall oxidation is performed before the gap-filling process. By reviewing the electrical properties of n- and p-MOSTs, it has been confirmed that INWE of n-MOST can be easily suppressed without any problem in p-MOST, and the uniformity of parameter can be remarkably improved by this method. Also, the gate oxide integrity and the junction leakage current have been evaluated in the device reliability point of view, and it is confirmed that there are no problems to use this technique in STI technology.