论文标题
探索删除植入的$^{210} $ pb和$^{210} $ po污染的方法的探索
Exploration of Methods to Remove Implanted $^{210}$Pb and $^{210}$Po Contamination from Silicon Surfaces
论文作者
论文摘要
检测器成分表面上的放射性污染物可能是寻找罕见过程的物理实验的背景事件的问题来源。接触ra是一个特定的问题，因为它可能导致相对较长的$^{210} $ pb（和后代）被植入显着的地下深度，从而使删除具有挑战性。在本文中，我们介绍了对清洁处理的广泛探索，以删除植入的$^{210} $ pb和$^{210} $ po污染硅的污染，这是在几个罕见的事件搜索中使用的重要材料。我们首次证明热处理（“烘焙”）可以有效地减轻这种表面污染，结果1200 $^{\ circ} $ c烘烤与完美的去除一致。我们还使用湿化学和基于等离子体的方法报告结果，这些方法表明，如果蚀刻深度足够侵略性，则蚀刻可以非常有效。我们对清洁方法的调查表明，在探测器构造的不同阶段中考虑了多种方法，以使有效地去除$^{210} $ pb和$^{210} $ po po表面污染的灵活性更大
Radioactive contaminants on the surfaces of detector components can be a problematic source of background events for physics experiments searching for rare processes. Exposure to radon is a specific concern because it can result in the relatively long-lived $^{210}$Pb (and progeny) being implanted to significant subsurface depths such that removal is challenging. In this article we present results from a broad exploration of cleaning treatments to remove implanted $^{210}$Pb and $^{210}$Po contamination from silicon, which is an important material used in several rare-event searches. We demonstrate for the first time that heat treatments ("baking") can effectively mitigate such surface contamination, with the results of a 1200 $^{\circ}$C bake consistent with perfect removal. We also report results using wet-chemistry and plasma-based methods, which show that etching can be highly effective provided the etch depth is sufficiently aggressive. Our survey of cleaning methods suggests consideration of multiple approaches during the different phases of detector construction to enable greater flexibility for efficient removal of $^{210}$Pb and $^{210}$Po surface contamination
