Development of carbon stripper foils for J-PARC Accelerators

十多年来，我们用重离子束溅射方法研制出了厚度为1.2μg/cm~2的超长寿命碳剥离膜。这种厚度的薄片主要用于100-200keV/u的重离子束。最近，高能负质子和重离子加速器开始使用厚度超过100μg/cm~2的碳剥离薄片。然而，重离子束溅射方法不能成功地制备厚度大于50μg/cm~2的薄膜，这是因为在溅射过程中碳颗粒从衬底上崩塌下来。重现率低于25%。收到的碳箔样品存在表面缺陷。然而，通过在溅射过程中引入衬底加热器来消除这些缺陷。在这份手稿中，我们描述了一种重复性很强的方法，即用氪和氙气溅射重离子束来制备厚碳剥离箔。

For over a decade, we have developed super long-lived carbon stripper foils of 1.20μg/cm2 thickness by the heavy ion beam sputtering method. Foils of this thickness are mainly used for heavy ion beams of 100-200 keV/u. Recently, high energy negative proton and heavy ion accelerators have started to use carbon stripper foils of over 100μg/cm2 in thickness. However, the heavy ion beam sputtering method was unsuccessful in production of foils thicker than 50μg/cm2 as resulted in the collapse of carbon particles from substrates during sputtering process. The reproduction probability was less than 25%. The samples of the carbon foil received had surface defects. However, the defects were eliminated by introduction of a substrate heater during sputtering process. In this manuscript we describe a highly reproducible method for thick carbon stripper foils by a heavy ion beam sputtering with krypton and xenon gases.