磁头折片组合清洗技术研究-机械工程专业毕业论文.docx

Classified Index: TH162 : 621
Dissertation for the Master’s Degree of Engineering
RESEARCH OF CLEANING TECHNIQUE FOR HEAD GIMBAL ASSEMBLY
Candidate: Bai Meng
Supervisor: Prof. Li Bing
Asst. Supervisor: Sr. Manager Zhang Qingwen Academic Degree Applied for: Master of Engineering Specialty: Mechanical Engineering
Affiliation: SAE ics(.) Ltd.
Date of Defence: December, 2013
Degree-Conferring-Institution: Harbin Institute of Technology
摘 要
硬盘中存取数据的核心部件是磁头和磁碟,磁头装配在磁头折片组合(Head Gimbal Assembly,简称 HGA)上,当硬盘开始工作时,磁碟高速旋转产生浮力, 使 HGA 悬浮于磁碟上方。随着硬盘技术的飞速发展,磁头的尺寸越来越小,HGA 磁头在碟片上的飞行高度越来越低,只有几纳米,如果此时有尘粒在磁头上,可能造成磁头与磁碟的撞击而损坏硬盘、丢失重要数据。因此对磁头的洁净度有很高要求。超声波清洗工序是 HGA 生产中保证 HGA 洁净度的重要工序,超声波清洗工艺很大程度上决定着 HGA 的品质,要求不仅能去除 HGA 上的尘粒、污渍,而且对 HGA 没有损伤或破坏。
分析超声波清洗的机理,建立 HGA 的 3 维模型,对于目前应用的 6 款超声波,模拟在其高频振动下 HGA 受到的应力,并通过实验获得不同超声波在不同输出功率条件下对 HGA 锡球的损坏程度。超声波输出功率越高,越容易损伤 HGA 的锡球;功率输出低于 70%时,有一款超声波的风险比较高。超声波对磁头的表面也有影响,在去离子纯水中,频率范围集中的超声波容易使磁头表面一些位置出现白色斑点,经过表面分析,发现是钛的氧化物,所以要避免这些超声波用于漂洗工序。清洗剂也对磁头表面有影响,经某些清洗剂清洗后,会在磁头表面形成黑色圆斑,通过表面分析得出黑斑是清洗剂残留形成的,优化工艺时要选用无影响的清洗剂。由于清洗剂溶液在一定时间内是循环使用的,为了降低清洗中产生的二次污染,需要性能好的过滤器。建立实验模型,分别研究具有不同过滤膜的 4 种过滤器的性能,选出最合适的过滤器。

关键词:磁头;超声波;清洗剂;过滤器



I
Abstract
The key parts of a Hard Disk Driver are the head and the media. The head is assembled on the Head Gimbal Assembly, which is called HGA simply. When a HDD is working, the media is rotating with a high speed, the HGA can fly above the media. With the development of HDD technology, the head of HGA is ing smaller and smaller. And the flying height is ing smaller and smaller too, only several nanometers. If there are particles on the head, they would cause scratch on the head and the media, then damage the HDD and the important data . So the cleanliness of HGA is very strict. Cleaning process is an important process of HGA production to ensure the cleanliness of HGA. Cleaning is important to the quality of HGA. Not only require it to have good efficiency, but also to be no damage to HGA.
The ultrasonic cleaning