Some imparity of crystal lattice can exist because of the heavy doping of silicon

so it can cause residual stress.To direct this problem

the strain caused by heavy doping is analysed by means of research in deflection curve of heavily boron-doped monocrystalline silicon cantilever.The relationship between deflection curve and dimensions of cantilevers has been studied

the length doesn’t affect the curve

but the width does

the smaller is the width

the steeper is the curve.Suppose the deflection is caused by bending moment

and the curve is simulated.The residual stress is about 1×107Pa.