Negative Electron Affinity GaAs as a Thermoelectric Cooler Element

The goal of this program is to create a prototype thin film superlattice thermoelectric cooler incorporating a parasitic heat leakage path defeating vacuum break via use of a negative electron affinity photoemitter surface as a free electron current source and to demonstrate its operation in a standalone vacuum system. In this work, a negative electron affinity surface will be qualified as sufficient to generate the requisite transport current in a thermoelectric coolerfriendly geometry, the thermal clean and activation process effects on the thin film superlattice layers and vice versa will be characterized, the best terminating photoemissive layer, GaAs or amorphous SiGe will be determined, the GaAs release layer and the GaAs/thin film superlattice interface and growth performance will be optimized via continued measurement and process feedback, cooling tests in a system allowing rapid sample turnaround will be performed and a prototype standalone system to demonstrate the device function will be constructed.