New primary standards and traceability for radiometry (NEWSTAR) (completed)
About the project
The overall objective is to support JRP SIB57 NEWSTAR in improving the predictability of the responsivity of PQEDs.
The scientific and technical objectives are:
- To develop a 3D model as a basis for the design of new diodes. This is essential to define the parameters for the new batch of photodiodes which will be manufactured subsequently.
- To measure the relationship between the fixed oxide charge and the effective lifetime of e-h pairs in order to estimate the optimum surface charge density that these devices should be manufactured with. Long e-h pair lifetime is desirable to achieve a photodiode with low internal quantum deficiency. High resistivity p doped wafers will be purchased, the fixed oxide charge will be gradually increased through different techniques and the e-h lifetime measured after each process. This will increase the understanding of the recombination mechanisms.
- To improve the reliability and robustness of the actual physical parameters used as input to the model, by measuring the doping profiles of the connection rings of the PQED diodes, the charge density and e-h pair lifetime of the photodiodes from the three different manufacturing rounds.
- To develop 3D computer models jointly with JRP-Partner JV and to perform simulations of the responsivity of the photodiodes from the different processing rounds at different temperatures and reverse bias. In order to estimate the uncertainty in the predictions the different input parameters will be varied within reasonable tolerances and the variation in the output responsivity observed.
- To compare the predictability of the responsivity obtained from the modelling and the simulations with characterisations and measurements made in JRP SIB57 NEWSTAR. This will give confidence that the predicted responsivity actually agrees with the measurements.
This project is funded by the European Union