A linear-shaped module based on Si-Ge alloys has been made for thermoelectric generation. The module is designed for generating electricity by exhaust heat of, e.g., plants, furnaces or automobiles. The module consists of 9 couples of p- and n-type Si-Ge alloy-based thermoelectric semiconductors. Carbon layers are made on both sides of the p- and n-type elements, and then the elements are electrically connected in series using Mo electrodes by blazing method. The size of the module is approximately 3.5 mm in width, 70 mm in length and 9.3 mm in height. Maximum power of the module was 2.0 W at a temperature difference of 509 K between the hot and cold sides of the module. A variation of generating power was measured for 150 modules. Maximum power of every module-block consisting of 10 modules was evaluated at a temperature difference of 400 K. The maximum power of the module-blocks was varied from 6.9 W to 8.7 W. After conducting a 200-hour heating test in Ar at 873 K, an averaged relative change of maximum power for 5 modules was less than 3% of the initial value. The potential advantages of the linear-shaped module compared with a 2-dimensionally shaped module, e.g., a plate, are as following: it gives design flexibility in electric circuits, because the linear-shaped module is very compact, and it can be used for heat sources whose surfaces are curved, and it can reduce deformation of the module caused by the temperature difference.
