Analysis of implanted layer in silicon for semiconductor device processing

A description is given of a technique and scheme developed from basic physical principles for analyzing and predicting implanted and redistributed profiles of common dopants such as boron, arsenic, phosphorus, and antimony. Basis of the scheme is a well known diffusion equation with initial conditions determined from the implant parameters. Various effects that must be considered for accurate and reliable prediction of the impurity distribution and sheet resistance variation of the implanted layers are the initial distribution, partial electrical activation and complex formation, concentration dependent, temperature dependent impurity diffusion coefficients and carrier mobilities, orientation, species dependent segregation of impurities at oxide-Si interface. The scheme in addition to including these effects considers process conditions such as temperature orientation dependent oxidation and has flexibility of handling heat treatment sequences in different ambient and at different temperatures. The numerical scheme presents the total and electrically active impurity depth distributions, sheet resistance of the layer, junction depths, and thickness of oxide grown in a form that is usable for process design optimization and sensitivity analysis. The results are in well agreement with data obtained by experimental techniques