Reaction of alkenes with hydrogen-terminated and photooxidized silicon surfaces. A comparison of thermal and photochemical processes.
Reaction of alkenes with hydrogen-terminated and photooxidized silicon surfaces. A comparison of thermal and photochemical processes.
复制标题
烯烃与氢封端和光氧化硅表面的反应。
作者：
T. Mischki;R. Donkers;B. Eves;G. Lopinski;D. Wayner
通过光掩膜紫外辐照对端氢Si（111）进行无试剂微图图化已被证明是制备有序双组分单层的一种方便策略。该技术的成功取决于烯烃与表面端氢区和光氧化区反应的不同速率。单分子层的形成可以在热或光化学条件下完成。观察到，在纯烯烃溶液（Rayonet, 300 nm）照射下反应3小时后，可以获得预期的图案表面，而热条件（150℃）导致图案保真度部分损失。采用接触角、椭偏仪、傅里叶变换红外光谱、高分辨率电子能量损失谱和x射线光电子能谱等方法研究了氧化硅和端氢硅在热光化学引发下的单层性质和形成过程。结果表明，烯烃以酸催化的方式在硅表面与硅醇基团相结合：一旦附着在硅表面，硅就会氧化碳氢化合物。
Reagentless micropatterning of hydrogen-terminated Si(111) via UV irradiation through a photomask has proven to be a convenient strategy for the preparation of ordered bicomponent monolayers. The success of this technique relies upon the differential rate of reaction of an alkene with the hydrogen-terminated and photooxidized regions of the surface. Monolayer formation can be accomplished under either thermal or photochemical conditions. It was observed that, after 3 h, reaction in neat alkene solution irradiation (Rayonet, 300 nm) afforded the expected patterned surface, while thermal conditions (150 degrees C) resulted in a partial loss of pattern fidelity. Monolayer properties and formation were studied on oxidized and hydrogen-terminated silicon under thermal and photochemical initiation, by contact angle, ellipsometry, Fourier transform infrared spectroscopy, high-resolution electron energy loss spectroscopy, and X-ray photoelectron spectroscopy. Results show that alkenes add to silanol groups on the silica surface in a manner consistent with acid catalysis: once attached to the surface, the silica oxidized the hydrocarbon.