Patent ID: 6285970
Filing Date: 2001-09-04
Classification: G06F

Abstract:
A method of fabricating a semiconductor device including simulating silicon oxidation to determine a time-dependent shape change of a Si region and a SiO.sub.2 region connected to said Si region in an oxidation process, said simulating silicon oxidation comprising the steps of:(a) configuring nodes on a simulation region including a Si region and a SiO.sub.2 region, said SiO.sub.2 region connected to said Si region to form a Si/SiO.sub.2 interface;(b) solving a diffusion equation of said oxidant at said individual nodes in said SiO.sub.2 region to calculate a surface concentration of said oxidant at said Si/SiO.sub.2 interface, resulting in a first value of said surface concentration of said oxidant at each of said nodes in a present time step;(c) adjusting said first value of said surface concentration of said oxidant at each of said nodes in said SiO.sub.2 region to generate a second value of said surface concentration of said oxidant at each of said nodes in said SiO.sub.2 region in said present time step;(d) calculating a thickness increase of said SiO.sub.2 region using said second value of said surface concentration of said oxidant at each of said nodes in said SiO.sub.2 region in said present time step;(e) calculating a new position of said Si/SiO.sub.2 interface in said present time step using said thickness increase of said SiO.sub.2 region obtained in said step (d); and(f) calculating shape deformations of said Si region and said SiO.sub.2 region using said new position of said Si/SiO.sub.2 interface obtained in said step (e).wherein said steps (a) to (f) are repeated from a first time step to a last time step at intervals of a time increment,wherein in said step (c) of adjusting said first value of said surface concentration of said oxidant in said present time step, said second value of said surface concentration of said oxidant is set as zero with respect to one of said nodes where said thickness increase of said SiO.sub.2 region obtained in said step (d) has a value equal to or less than a specific small value and at the same time, said first value of said surface concentration of said oxidant is stored for a next time step,wherein said stored first value of said surface concentration of said oxidant is added to a first value of said surface concentration of said oxidant obtained in said next time step, thereby producing a second value of said surface concentration of said oxidant in said next time step, said second value of said surface concentration of said oxidant thus produced being used in the following step (d) of calculating said thickness increase of said SiO.sub.2 region in said next time step, andwherein in said step (c) of adjusting said first value of said surface concentration of said oxidant in said present time step, said second value of said surface concentration of said oxidant is set as said first value of said surface concentration of said oxidant with respect to one of said nodes where said thickness increase of said SiO.sub.2 region obtained in said step (d) has a value greater than said specific small value.