The　early　stage　oxidation　in　Si(100)　surface　has　been　investigated　in　this　work　by　a　reactive　force　field　molecular　dynamics　(ReaxFF　MD)　simulation,　manifesting　that　the　oxygen　transport　acted　as　a　dominant　issue　for　initial　oxidation　process.　Due　to　the　oxidation,　a　compressive　stress　was　generated　in　the　oxide　layer　which　blocked　the　oxygen　transport　perpendicular　to　the　Si(100)　surface　and　further　prevented　oxidation　in　the　deeper　layer.　In　contrast,　thermal　actuation　was　beneficial　to　the　oxygen　transport　into　deeper　layer　as　temperature　increases.　Therefore,　a　competition　mechanism　was　found　for　the　oxygen　transport　during　early　stage　oxidation　in　Si(100)　surface.　At　room　temperature,　the　oxygen　transport　was　governed　by　the　blocking　effect　of　compressive　stress,　so　a　better　quality　oxide　film　with　more　uniform　interface　and　more　stoichiometric　oxide　structure　was　obtained.　indeed,　the　mechanism　presented　in　this　work　is　also　applicable　for　other　self-limiting　oxidation　(e.g.　metal　oxidation)　and　is　helpful　for　the　design　of　high-performance　electronic　devices.　(C)　2017　Elsevier　B.V.　All　rights　reserved.