In situ in-reactor testing of potential bolometer materials for ITER plasma diagnostics

We present the results of in-reactor irradiation up to a total dose of 0.01 dpa [Al] of two prototype bolometers with a Pt-meander on AlN and Al2O3 ceramic substrates to test their radiation resistance. A dedicated vacuum capsule with a hot stainless steel holder for the bolometers was designed and fabricated in order to allow irradiation at 400 °C in vacuum. The holder was heated with gamma-radiation. The Pt-meander and substrate electrical resistances were measured in situ. Direct electrical measurements show that the Pt-meander on both substrates will sustain radiation fluences up to 0.001 dpa [Al]. Post-radiation inspection indicates that they will survive up to at least 0.01 dpa [Al].