bonds at the grain boundaries i e the is surface electronic states and thus the electrical properties of the film the eventual poly ge layer thickness is dependent on the device design therefore the film morphology and structure such as the grain size and orientation affect the material electrical properties which need to be considered to optimize a device design on test structures test measurements afm sem measurement u03bc raman measurement and xtem measurement provide insights on surface morphology crystalline quality and residual strain status metrology measurements provides information on growth rate and material homogeneity these measurements are performed on and off the window openings in step 230 i e on the film deposited on the si substrate or on the silicon oxynitride mask respectively at step 260 the poly crystalline growth is not selective and a ge pad definition step is typically added a chlorine based cl based etch can be used in order to remove the ge deposited outside the openings of windows in the first silicon oxynitride layer alternatively an in situ etch using an hcl hydrogen mixture could be used metrology and surface analysis measurement is used to confirm a complete removal of unwanted material if poly si has been used as the seed layer it will be removed by this process step as for test structures test measurements material homogeneity is monitored on a structure suitable for metrology measurements both over the wafer and on a window opening.