Minimizing recombination at semiconductor surfaces is required for the accurate determination of the bulk carrier lifetime. Proton donors, such as hydrofluoric acid and superacids, are well known to provide highly effective short-term surface passivation. We demonstrate here that aprotic solutions based on bis(trifluoromethanesulfonyl)methane (TFSM) in hexane or pentane can also result in excellent passivation of (100)-orientation silicon surfaces. We show that the optimized TFSM-pentane passivation scheme can measure effective lifetimes up to 20 ms, with a surface recombination velocity of 1.7 cm s−1 at an excess carrier density of 1015 cm−3. Fitting injection-dependent lifetime curves requires chemical passivation and field effect passivation from a negatively charged layer with a charge density of 1010–1011 q cm−2. The slightly higher recombination velocity of 2.3 cm s−1 measured with TFSM-hexane can be explained by a lower charge density in the passivating layer, suggesting that the steric hindrance associated with the solvent size could play a role in the passivation mechanism. Finally, phosphorus nuclear magnetic resonance experiments confirm that TFSM-based solutions have Lewis acidity without being superacids, which opens up opportunities for them to be used in materials systems sensitive to superacidic environments.Minimizing recombination at semiconductor surfaces is required for the accurate determination of the bulk carrier lifetime. Proton donors, such as hydrofluoric acid and superacids, are well known to provide highly effective short-term surface passivation. We demonstrate here that aprotic solutions based on bis(trifluoromethanesulfonyl)methane (TFSM) in hexane or pentane can also result in excellent passivation of (100)-orientation silicon surfaces. We show that the optimized TFSM-pentane passivation scheme can measure effective lifetimes up to 20 ms, with a surface recombination velocity of 1.7 cm s−1 at an excess carrier density of 1015 cm−3. Fitting injection-dependent lifetime curves requires chemical passivation and field effect passivation from a negatively charged layer with a charge density of 1010–1011 q cm−2. The slightly higher recombination velocity of 2.3 cm s−1 measured with TFSM-hexane can be explained by a lower charge density in the passivating layer, suggesting that the steric hindrance a...

中文翻译：

---

通过非质子溶液对硅表面进行亚 2 cm/s 钝化

为了准确确定体载流子寿命，需要最大限度地减少半导体表面的复合。众所周知，氢氟酸和超强酸等质子供体可提供高效的短期表面钝化。我们在这里证明了基于双（三氟甲磺酰基）甲烷（TFSM）在己烷或戊烷中的非质子溶液也可以导致（100）取向硅表面的优异钝化。我们表明，优化的 TFSM-戊烷钝化方案可以测量长达 20 ms 的有效寿命，在 1015 cm-3 的过量载流子密度下表面复合速度为 1.7 cm-s-1。拟合注入相关寿命曲线需要来自电荷密度为 1010–1011 q cm-2 的带负电层的化学钝化和场效应钝化。用 TFSM-己烷测得的 2.3 cm s-1 稍高的复合速度可以用钝化层中较低的电荷密度来解释，这表明与溶剂尺寸相关的位阻可能在钝化机制中起作用。最后，磷核磁共振实验证实基于 TFSM 的溶液具有路易斯酸性而不是超酸，这为它们在对超酸环境敏感的材料系统中使用开辟了机会。散货船寿命。众所周知，氢氟酸和超强酸等质子供体可提供高效的短期表面钝化。我们在这里证明了基于双（三氟甲磺酰基）甲烷（TFSM）在己烷或戊烷中的非质子溶液也可以导致（100）取向硅表面的优异钝化。我们表明，优化的 TFSM-戊烷钝化方案可以测量长达 20 ms 的有效寿命，在 1015 cm-3 的过量载流子密度下表面复合速度为 1.7 cm-s-1。拟合注入相关寿命曲线需要来自电荷密度为 1010–1011 q cm-2 的带负电层的化学钝化和场效应钝化。用 TFSM-己烷测得的 2.3 cm s-1 稍高的复合速度可以用钝化层中较低的电荷密度来解释，这表明空间位阻...