Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Langmuir. 2013 Apr 30;29(17):5145-9. doi: 10.1021/la400849j. Epub 2013 Apr 16.
Gallium nitride, with a thin passivating layer of Ga2O3, has been functionalized with octadecyltrichlorosilane (OTS) and aminopropyltriethoxysilane (APTES) self-assembled monolayers (SAMs). Water contact angles, atomic force microscopy, and X-ray photoelectron spectroscopy were used for characterization of the bare and functionalized surfaces. The SAMs are stable in acetonitrile, but both the hydrophobic OTS SAM and the hydrophilic APTES SAM completely desorb after 1-24 h of immersion in water and common buffers. The concentration of gallium in solution after a clean GaN chip is immersed in water is consistent with dissolution of roughly one monolayer of interfacial gallium oxide. Dissolution of this oxide layer could account for the loss of SAMs from GaN surfaces.
氮化镓（GaN）表面用氧化镓（Ga2O3）的薄钝化层进行了功能化，并用十八烷基三氯硅烷（OTS）和氨丙基三乙氧基硅烷（APTES）自组装单层（SAM）进行了功能化。水接触角、原子力显微镜和 X 射线光电子能谱用于对裸表面和功能化表面进行表征。SAM 在乙腈中稳定，但疏水性 OTS SAM 和亲水性 APTES SAM 在水和常见缓冲液中浸泡 1-24 小时后完全解吸。干净的 GaN 芯片浸入水中后溶液中镓的浓度与界面氧化镓约一个单层的溶解一致。这种氧化物层的溶解可能是 GaN 表面 SAM 损失的原因。
