S-CALe Up - Self-calibrating photodiodes for UV and exploitation of induced junction technology

Project structure

The project consists of four technical work packages and two work packages for creating impact and managament. The technical work packages are desicribed briefly below.

• WP1: Improved modelling and simulation. The aim of this work package is to improve the 3D simulation models of the internal quantum deficiency (IQD) of photodiodes produced in the 18SIB10 chipS·CALe project and those developed in this project to predict IQD from 200 nm to 1050 nm with an uncertainty approaching 1 ppm in the optimum spectral region. The simulation model developed in the 18SIB10 chipS·CALe project showed a good prediction of photodiode IQD from 400 nm to 850 nm with an uncertainty of 30 ppm or better. However, the model uses only 1/8 of the photodiode structure and the experimental Gaussian beam needs to be converted to an equivalent flattop beam due to lack of computational facility. The 3D simulation model from the 18SIB10 chipSꞏCALe project is defined by fixed oxide charge (Qf), surface recombination velocity (SRV), doping concentration p and minority charge carrier lifetime (τ_bulk). As the improved simulation model will cover long wavelengths up to 1050 nm, additional parameters such as wafer thickness, backside reflectance etc. will be studied.
• WP2: Applications of photodiodes and detectors with very low spectral response uncertainty. The aim of this work package is the exploitation of PQEDs with very low spectral responsivity uncertainty in the 400 nm to 850 nm range as built-in references in three key applications: photometry without V(λ) filters, fibre optics and photonic integration and self-referenced optical power meter.
• WP3: Developing photodiodes with improved UV stability and responsivity. The aims of this work package are to develop and manufacture photodiodes with improved performance and stability in the UV regime as a spectral responsivity standard from 200 nm to 400 nm and to provide detectors capable of achieving the 1 ppm prediction uncertainty.
• WP4: Establishing spectral response scales from 200 nm to 1050 nm with PQEDs and improved dual-mode detectors. The aim of this work package is to establish predictable spectral response scales from 200 nm to 1050 nm. which is the range covered by the CCPR key comparisons K2.c (spectral responsivity in the range 200 nm to 400 nm) and K2.b (spectral responsivity in the range 300 nm to 1000 nm) and has great importance for photometric and radiometric applications. To this end, both induced junction photodiodes manufactured in 18SIB10 chipSꞏCALe project and photodiodes manufactured in the current project will be characterised to cover the stated range. In order to meet the responsivity goals in the UV range and potentially establish a technique to cover the CCPR-K2.a range from 900 nm to 1600 nm in the future, a packaging technology for dual-mode detectors with a heating equivalence better than 0.03 % will be developed, which will also be suitable to exploit photodiodes other than silicon developed in the project.