A technology for a device prototyping based on electrodeposited thermoelectric V-VI layers

A work shared between the Laboratoire d'Electrochimie des Materiaux (LEM) and the Fraunhofer - Institute for Physical Measurement Techniques (IPM) led to propose a technology for the fabrication of thermoelectric devices based on electrodeposited V-VI layers. We present this device technology based on a two-wafer concept to control independently the properties of n and p-type bismuth telluride compounds. The electrodeposition technology was developed and performed by the LEM and showed the ability of depositing n-type layers on 4" structured wafers. The different steps of a technological route for a device with processes commonly used for microelectronics were defined and developed by the IPM. The wet chemical and reactive ion etching techniques were successfully applied onto the electroplated layers to structure the thermoelectric legs. Our work evidenced the ability to fabricate half-devices on 4" level by combining the electrodeposition of thermoelectric films and the structuring technologies. Bonding two complementary sides of a device together can finish the fabrication process. All the steps except the bonding technology were tested and have proven to be practicable.