Evaluation of pulse magnetron sputtered Ge films doped with antimony for sensors application

The results of investigations concerning the thermoelectric properties and the structure of Ge sputtered films under pulsed voltage operation of magnetron are reported. The film properties are discussed as a function of doping with antimony (0.5–1.7 at.%), the substrate temperature during deposition (623–950 K) and the effective power supplying (0.18–0.4 W). Almost all as-deposited films were polycrystalline and contained crystallites of Ge phase of diamond type. The attractive feature was the possibility of formation of Ge (Sb) films with p- and n-type conduction. The Seebeck coefficients in the range of −550 to 400 μV K−1 were achievable. The results indicated that the internal stresses in Ge phase changed from compression to tension (−2.6×108 to 1.8×108 Pa) corresponding with change of conduction type. It can be modified by the deposition conditions or kind of substrate. The experimental results are discussed in terms of microstructure changes. The proper deposition conditions for optimizing the efficiency of thermoelectric power can be obtained.