Bıyıklı, NecmiKimukin, I.Aytur, O.Özbay, Ekmel2016-02-082016-02-0820041041-1135http://hdl.handle.net/11693/24267We report solar-blind AlxGal1-xN-based heterojunction p-i-n photodiodes with low dark current and high detectivity. After the p+ GaN cap layer was recess etched, measured dark current was below 3 fA for reverse bias values up to 6 V. The device responsivity increased with reverse bias and reached 0.11 A/W at 261 nm under 10-V reverse bias. The detectors exhibited a cutoff around 283 nm, and a visible rejection of four orders of magnitude at zero bias. Low dark current values led to a high differential resistance of 9.52 × 1015 Ω. The thermally limited detectivity of the devices was calculated as 4.9 × 1014 cm · Hz1/2W-1. © 2004 IEEE.EnglishAluminum gallium nitrideDark currentSapphire substrateSpectral responsivityCurrent densityCurrent voltage characteristicsElectric current measurementGallium nitrideHeterojunctionsMetallorganic chemical vapor depositionOhmic contactsPhotodetectorsPlasma enhanced chemical vapor depositionReactive ion etchingSemiconducting aluminum compoundsSubstratesPhotodiodesArticle10.1109/LPT.2004.829526