Effects of surface plasma treatment on n-GaN ohmic contact formation

The origin of the residual conductivity of GaN films on ferroelectric materials

“…Ga3d peaks were detected using XPS high energy-resolution scans with an energy resolution of 0.05 as determined for the equipment used, which is consistent with literature reports for similar instruments [20]. Fig.…”

“…The data indicates that the GaN films in the four samples are oxidized, as Ga-O-N and the Ga/N ratios are higher than the designated values. The nitrogen-deficient GaN films are not necessarily interpreted as nitrogen vacancies because the missing nitrogen atoms are replaced with oxygen atoms, which act as n-type donors [20].…”

GaN Nanowire Carrier Concentration Calculated from Light and Dark Resistance Measurements

“…Although Yan et al 21 have produced contacts to GaN film with contact resistivity as low as 10 À7 X cm 2 , most reported contact resistivities for GaN films are in the high 10 À6 X cm 2 or low 10 À5 X cm 2 range. [36][37][38] Nanowire contact resistivities have been reported around 1 9 10 À5 X cm 2 . 23,24 This discrepancy was resolved by applying a transfer length correction in our model.…”

Effect of oxygen plasma treatment on nonalloyed Al/Ti-based contact for high power InGaN/GaN vertical light-emitting diodes

“…This enables Al/Ti-based contacts to the plasma-treated n-GaN to produce good Ohmic behavior which arises from the presence of donorlike defects like nitrogen vacancies (V N ) in the near surface region. [20][21][22][23] However, plasma treatment without HCl cleaning process (type C) in this study increased V F , which is ascribed to an increase in series resistance due to the insertion of a thin insulation layer at the metal/n-GaN interface. Type D, treated with O 2 plasma followed by HCl cleaning, exhibited sufficiently low V F with steeper I-V characteristics (not shown here).…”