Highly versatile ultrasonic system for dependable final cleaning of microstructures

不得有大于1µm的颗粒

Technological advances in the field of microstructures and the need to process larger substrates called for the installation of a new final cleaning system at 波格游戏 Präzisionsoptik Gera. The equipment solution proposed by UCM AG won the customer's approval. It makes it possible to clean both untreated wafers as well as structured and coated substrates. The cleanliness specification stipulating "no particle larger than 1 µm" is reliably fulfilled.

1991年，德国的蔡司工厂倒闭, a group of former high-level executives led a management buyout to preserve and develop the long tradition of optical manufacturing at Gera, 由此诞生了波格游戏 Präzisionsoptik Gera GmbH. 如今，该公司拥有140名员工. 它发展并产生, 一方面，一方面, 定制光学精密零件, components and devices for the entire optical range of the spectrum. These items are used by customers all over the world in the fields of mechanical engineering, 测量技术, 工业图像处理, 医疗设备, 激光技术, 还有半导体和航空航天工业. 另一方面, the company has gained international renown as a manufacturer of both standardized and custom optical microstructures, e.g., net grid and scale graticules, USAF resolution targets, pinhole apertures and calibration targets. In this segment, 波格游戏 can handle all development and production process in-house. "We recently expanded our fabrication of microstructures in terms of both the range of technological options and the size of substrates we are capable of handling. 因此, 需要一个新的最终清洗系统。”, Jan Schubach报道, 波格游戏的总经理之一.

要求最大程度的清洁

波格游戏's optical microstructures are made chiefly from B 270 glass and quartz glass, 以及从陶瓷和玻璃陶瓷基板. 最后的清洁步骤，用来清除灰尘, ultra-fine residue of polishing products and fingerprints is mandatory both with untreated substrates and after adding the structure and coating. Since the structures applied to the substrates measure only 2 µm in some cases, the cleanliness specification requires that no particle should be larger than 1 µm. 波格游戏 developed a solution for these very exacting cleaning tasks jointly with an external consultant while discussing its technology with various equipment makers.

一个通用的清洁系统，而不是多种特殊类型

„We were looking at different cleaning concepts for special uses such as cleaning masks or a specific substrate configuration for the semiconductor industry. In all likelihood, we would have needed three different systems to meet our needs. 这促使我们与UCM取得联系. We already possessed one cleaning system from this equipment maker, 我们的顾问, 太, had gathered good experience with the company in another project", Jan Schubach解释道. 瑞士UCM公司, 生态清洁组织的成员, revised and adapted the equipment concept together with 波格游戏 and the consultant. “UCM非常灵活地处理了我们的建议, drawing on their own extensive experience in the manufacture of cleaning systems for optical products", 总经理记得.

The new ultrasonic cleaning line comprises a total of eleven stations, 包括7个浸入式水箱. 这些设计用于以下工艺步骤:湿加载, 多频超声波(40和80 kHz)清洗, megasonic清洁, 冲洗, fine-冲洗, 红外干燥在一个分度带式输送机, 和卸载.

The wet loading operation and all cleaning and 冲洗 processes are performed with demin. (完全脱盐的)水. 这取决于清洁程序, 冲洗水在级联循环中使用, 被丢弃的, 或者通过一个单独的排水管. 这种方法有助于提高清洗质量, as does the four-sided overflow feature developed by UCM which is used on all tanks. 清洗液或漂洗液从下面进入储罐, 向上移动，然后从四面溢出. As a result, foreign matter removed from the product will be discharged from the tanks straight away. This avoids re-contamination during unloading of parts while also preventing the formation of dirt pockets in the tanks. In addition, the substrates are treated very thoroughly and uniformly.

冲洗槽有另一个特殊的设计特点. Water is pumped into these tanks at high pressure so as to cause turbulence. 这就足够了, 与产品运动相结合, 目前在没有超声波辅助的情况下冲洗基材. 然而, the mechanical equipment and control system are both prepared to support a future integration of ultrasound so that the user will be able to respond quickly and flexibly should more exacting demands arise.

在洁净室全自动清洗

清洁系统集成在洁净室中. 待处理的基材, 尺寸达10英寸的, are placed manually in the system's handling racks in special cassettes. The operator then selects the appropriate part-specific cleaning program. This is stored in the system's controller and determines which stations will be used in each case and which treatment parameters – e.g., ultrasonic power and frequency, dwell time – should be set for each tank. In order to ensure accurate compliance with the defined treatment duration at each station, 柔性控制系统支持“优先时间”输入。. „We are currently working with 10 programs for the diverse substrates and have been achieving excellent results with all cleaning tasks from the very start. The cleaning system has been operating smoothly since its handover in March 2015. 事实上, we haven't seen any of the teething troubles usually encountered with such complex equipment", 简·舒巴赫满意地指出.


作者:Doris Schulz