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Additional file 1: Supplementary Table 1. Time varying Performance of baseline biomarkers using ID approach (AUC with 95% CI).

Additional file 2: Supplementary Table 2. Time varying Performance of updated biomarker using ID approach (AUC with 95% CI).

Additional file 4: Supplementary Table 4. Time varying Performance of updated biomarker using CD approach (AUC with 95% CI).

Additional file 3: Supplementary Table 3. Time varying Performance of baseline biomarkers using CD approach (AUC with 95% CI).

In this thesis chromium (Cr) incorporation during GaN growth by metal organic vapor phase epitaxy (MOVPE) was studied for the first time with the intention of producing a dilute magnetic semiconductor (DMS) with room temperature ferromagnetism. To this end the following growth parameters were investigated and optimized: carrier gas, precursor access and ratios, and growth temperature as well as post growth annealing. Also the effect of different H2/N2 carrier gas ratios on the undoped GaN buffer layer was explored. The N2 content in the carrier gas affected the growth mechanism of the GaN layer. The threading dislocation density as well as the sheet resistance increases with N2 content in the carrier gas. Cr-doped GaN (GaN:Cr) layers were grown on the optimised undoped GaN buffer layer. Uniform Cr distribution, good surface morphology and room temperature ferromagnetism were to be obtained. The inverted precursor access to the substrate promoted high Cr incorporation efficiency. A certain amount of H2 in the carrier gas was necessary to obtain coalesced surface morphology of GaN:Cr layers. The GaN:Cr layer grown at 950°C exhibited smooth surface morphology and enhanced Cr incorporation into the layer as well as ferromagnetic behaviour at room temperature. The Curie temperature (TC) was determined to be about 620 K. A high Cr/Ga source ratio increases the Cr concentration in the GaN:Cr layers and also increases the thermo-remanent magnetization. The use of post growth annealing at 700°C is advantageous for the magnetic properties.