Native Oxide Removal from InAlN Surfaces by Hydrofluoric Acid Based Treatment

Abstract

SUMMARYWe investigated the effects of chemical treatments for removing native oxide layers on InAlN surfaces by X-ray photoelectron spectroscopy (XPS). The untreated surface of the air exposed InAlN layer was covered with the native oxide layer mainly composed of hydroxides. Hydrochloric acid treatment and ammonium hydroxide treatment were not efficient for removing the native oxide layer even after immersion for 15 min, while hydrofluoric acid (HF) treatment led to a removal in a short treatment time of 1 min. After the HF treatment, the surface was prevented from reoxidation in air for 1 h. We also found that the 5-min buffered HF treatment had almost the same effect as the 1-min HF treatment. Finally, an attempt was made to apply the HF-based treatment to the metal-InAlN contact to confirm the XPS results.

Reduction of interface state density at SiO2/InAlN interface by inserting ultrathin Al2O3 and plasma oxide interlayers

“…Here the spectrum for the SiO 2 /InAlN interface was obtained at u ¼ 908, for which the photoelectron escape depth was 2.9 nm. The energy position, shape, and intensity of the O 1s spectrum from the InAlN surface before deposition, immediately after the BHF treatment, coincided with those for the O 1s spectrum from the HF-treated gold surface, which indicated that the corresponding component can be attributed to absorbed water molecules [20]. On the other hand, as shown in Fig.…”

Appropriate fabrication procedure for InAlN metal‐oxide‐semiconductor structures with atomic‐layer‐deposited Al2O3

“…As we have reported previously [7], the native oxide layer at the as-served InAlN surface consists of oxides and hydroxides of In and Al as shown in Fig. 4 Fig.…”

“…Thus, it is highly likely that the polycrystalline state of the annealed Al 2 O 3 layer affected the electrical properties for sample B. If the grain boundaries generated by uncontrolled polycrystallization are concentrated, a leakage current path is possibly generated [7]. For sample B, we found that the magnitude of the leakage current was dependent on the measurement position even on the same chip, as shown for the worst and the best cases in Fig.…”

Interface Investigation of High-Temperature-Annealed Ultrathin-ALD-Al₂O₃/InAlN Structures

“…1(a). Prior to the deposition of Al 2 O 3 , the native oxide layer on the air-exposed InAlN surface was removed by hydrofluoric acid solution followed by rinsing in deionized water [22]. The Al 2 O 3 layer was formed by ALD at 350 • C using H 2 O and trimethylaluminum.…”