Production and Investigation of Porous Si-Ge Structures for Thermoelectric Application

Mesoporous Si and Si-Ge are promising candidates for efficient thermoelectric converters needed for energy harvesting, e.g. from hot exhaust pipes of cars. Suitable mesoporous structures must meet a number of requirements concerning their geometry and processing costs, and suitable pore etching techniques have been developed. The paper addresses these issues, including the use of Si-Ge substrates from specially grown Si-Ge crystals. It is shown that most geometric and process requirements can be met by etching so-called current line pores under special conditions. First results concerning thermal and electrical properties are also presented.