steps can be performed at the same time ignored or added the steps outlined here use a broader and simpler method to describe the characteristics of the invention and should not be used to restrict the order and the number of times a particular step should be performed first a semiconductor device 100 is provided it has one or more pmos 101 and one or more nmos 102 the semiconductor device 100 generally speaking can be prepared using the normal standard cmos process on a silicon substrate 103 afterwards at least one high stress layer 200 is formed on the semiconductor device 100 as a cap layer of the pmos 101 and at least one nmos 102 the material of the high stress layer 200 can be for example silicon nitride other choices such as teos bpsg psg bsg sio2 and sio x n y are also possible the high stress layer 200 can be formed on the semiconductor device 100 using plasma enhanced chemical vapor deposition pecvd or low pressure chemical vapor deposition lpcvd the high stress layer 200 is then covered by photo resist 300 its position can be selected to be the one for pmos 101 or nmos 102 finally ion implantation is performed on the part of the semiconductor.