Influences　of　residual　stress　on　mechanical　properties　of　boron-doped　silicon　diaphragms　are　analyzed.　Considering　the　residual　stress,　the　total　stress　analytical　solutions　for　square-shaped　boron-doped　silicon　diaphragms　with　small　deflection　and　large　deflection　are　presented.　It　is　found　that　the　residual　stress　should　not　be　neglected　in　calculation　of　the　total　stress　for　diaphragms　with　large　ratio　of　edge　length　to　thickness.　The　load　limitation　P-max　of　the　square-shaped　boron-doped　silicon　diaphragms　is　calculated　based　on　the　total　stress　analytical　solution　and　the　Griffith　fracture　criterion.　The　results　agree　well　with　the　reported　experiments.　Many　micro-etchholes　were　found　on　the　surface　of　boron-doped　silicon　diaphragm　made　from　wet　etch　process,　and　these　holes　cause　great　degradation　of　the　load　limitation　P-max　compared　with　perfect　crystal　silicon　diaphragms.　(C)　2006　Elsevier　Ltd.　All　rights　reserved.