Radical-Driven Silicon Surface Passivation by Benzoquinone– and Hydroquinone–Methanol and Photoinitiators
Radical-Driven Silicon Surface Passivation by Benzoquinone– and Hydroquinone–Methanol and Photoinitiators
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DOI：
10.1021/acs.jpcc.7b05686
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发表时间：
2017-09
影响因子：
3.7
通讯作者：
Meixi Chen;James H. Hack;Abhishek Iyer;K. Jones;R. Opila
中科院分区：
文献类型：
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作者：
Meixi Chen;James H. Hack;Abhishek Iyer;K. Jones;R. Opila
这项工作证实，自由基中间体是醌氢醌/甲醇（QHY/ME）钝化硅表面的反应物种。分别研究了对苯醌（BQ）和对苯二酚（HQ）两个组分。BQ从甲醇中夺取氢原子成为半醌自由基（QH*）。这两个QH* 和由此产生的甲醇自由基是负责的大，瞬时增加少数载流子寿命在BQ/ME，获得最低的表面复合速度为1.6厘米/秒。HQ释放一个氢原子成为QH*。在苯环上含有较低电负性基团（Cl-或O-）的醌衍生物更容易形成自由基，钝化效果更好。这种自由基驱动的钝化机制也适用于其他自由基源。X射线光电子能谱（XPS）分析表明，BQ/ME处理1h后，BQ键占主导地位，甲醇键随浸泡时间的增加而增加，说明BQ/ME处理的反应机理为自由基反应。
This work confirms that radical intermediates are the reactive species in quinhydrone/methanol (QHY/ME) passivation on silicon surfaces. The two constituent parts, p-benzoquinone (BQ) and hydroquinone (HQ), have been studied separately. BQ abstracts the hydrogen atom from methanol to become semiquinone radicals (QH*). Both QH* and the resulting methanol radical are responsible for the large, instantaneous increase in minority carrier lifetime in BQ/ME, obtaining the lowest surface recombination velocity of 1.6 cm/s. HQ releases a hydrogen atom to become QH*. The quinone derivatives containing a lower electronegativity group (Cl— or O═) on the benzene ring form radicals more easily, and give better passivation results. This radical-driven passivation mechanism is also valid on other radical sources. X-ray photoelectron spectroscopy (XPS) supports the radical mechanism in the observation of dominating BQ bonding after 1 h of BQ/ME treatment, and increasing methanol bonding with increasing immersion time, re...