Dynamic magnetic information storage or retrieval – Head mounting – Disk record
Reexamination Certificate
2002-02-01
2004-02-10
Tupper, Robert S. (Department: 2652)
Dynamic magnetic information storage or retrieval
Head mounting
Disk record
Reexamination Certificate
active
06690547
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a suspension used in for example a hard disk drive (HDD) apparatus and for supporting a drive IC chip for a thin-film magnetic head element, to head gimbal assembly (HGA) with the suspension and to a manufacturing method of an HGA.
DESCRIPTION OF THE RELATED ART
In such HDD apparatus, the thin-film magnetic head element for writing magnetic information into and/or reading magnetic information from a magnetic disk is in general formed on a magnetic head slider flying in operation above a rotating magnetic disk. The slider is fixed at a top end section of the suspension.
Recently, recording frequency in the magnetic disk rapidly increases to satisfy the requirement forever increasing data storage capacities and densities in today's HDDs. In order to realize higher frequency recording, proposed is a chip-on-suspension structure of an HGA with a suspension for supporting both a slider and a drive IC chip of a driver circuit for the magnetic head element. According to this structure, since the length of lead lines from the driver circuit to the magnetic head element can be shortened, generation of unnecessary noises from the lead lines can be effectively suppressed resulting high frequency recording characteristics to improve. Also, it is possible to amplify a very faint output signal provided from a magnetoresistive effect (MR) read head element at a nearer position to the MR head element.
The drive IC chip used in such chip-on-suspension structure HGA is required to extremely downsize due to its mounting configuration. If the drive IC chip is so downsized, its surface area becomes greatly small causing extremely insufficient thermal radiation. Because a writing current flowing through the drive IC chip during recording operation is very large, this insufficient heat radiation of the drive IC chip will become a significant problem. In addition, since the drive IC chip is mounted on a suspension with a very small mounting space and also an electrical characteristics of the drive IC chip will be deteriorated due to noises caused by floating capacitance of its lead terminals at a higher frequency more than 500 MHz, it is necessary to fabricate the drive IC chip as a bare IC chip. Thus, the heat radiation performance of the drive IC chip will more decrease and a chip temperature will dependently increase.
Usually, a spring member of a suspension is formed by a leaf spring of a stainless steel. However, since the stainless steel has a lower thermal conductivity in comparison with that of other metal material and the stainless steel suspension is formed in a quite thin thickness, a sufficient thermal radiation effect cannot be expected when the suspension of the chip-on-suspension structure HGA is mainly made of the stainless steel.
As aforementioned, according to the conventional HGA with the chip-on-suspension structure has the following problems:
(1) Since the drive IC chip is extremely thin and small and therefore has a small surface area, it is difficult to effectively radiate a heat generated by itself;
(2) Since a stainless steel generally used for the spring member of the suspension has a relatively low thermal conductivity and an extremely thin thickness, no sufficient thermal radiation effect can be expected if the HGA is configured with a normal chip-on-suspension structure; and
(3) Since the drive IC chip is mounted on a surface of the suspension, which is faced to a magnetic recording medium, it is difficult to attach a thermal radiation mechanism directly to the drive IC chip itself.
If heat is generated in chip and it is not sufficiently radiated from the drive IC chip and thus the temperature of the drive IC chip highly increases, not only operations of the drive IC chip becomes unstable but also a thermal deformation of the drive IC chip may occur.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a suspension, an HGA and a manufacturing method of an HGA, whereby more effective heat radiation of a drive IC chip can be expected.
Another object of the present invention is to provide a manufacturing method of an HGA, whereby more effective heat radiation of a drive IC chip can be expected without substantially adding a new process to a conventional manufacturing process.
According to the present invention, a suspension includes a resilient flexure made of a stainless steel for supporting a magnetic head slider with at least one thin-film magnetic head element, a load beam made of a stainless steel, supporting the flexure, for applying a predetermined load to the magnetic head slider, a lead conductor member on which a drive IC chip with a circuit for the at least one thin-film magnetic head element is to be mounted, and a high-thermal-conductivity member made of a material with a higher thermal conductivity than that of the stainless steel and inserted between the lead conductor member and the load beam in a region containing at least a section on which the drive IC chip is to be mounted.
Also, according to the present invention an HGA includes a magnetic head slider with at least one thin-film magnetic head element, a resilient flexure made of a stainless steel, supporting the magnetic head slider, a load beam made of a stainless steel, supporting the flexure, for applying a predetermined load to the magnetic head slider, a drive IC chip with a circuit for the at least one thin-film magnetic head element, a lead conductor member on which the drive IC chip is mounted, and a high-thermal-conductivity member made of a material with a higher thermal conductivity than that of the stainless steel and inserted between the lead conductor member and the load beam in a region containing at least a section on which the drive IC chip is mounted.
The high-thermal-conductivity member with a higher thermal conductivity than that of the stainless steel is inserted between the lead conductor member and the load beam in a region containing at least a section on which the drive IC chip is to be or is mounted. Thus, not only a thermal capacity of the suspension can be increased but also heat generated from the drive IC chip can be transferred through this high-thermal-conductivity member and widely dissipated resulting the drive IC chip to effectively cool. Therefore, the temperature of the drive IC chip itself can be decreased and also elevation of the local temperature of the suspension around the drive IC chip can be suppressed. As a result, a stable operation of the drive IC chip can be expected, a thermal deformation of the suspension can be prevented, and a serious heat effect to the thin-film magnetic head element can be prevented.
It is preferred that the lead conductor member is formed on the flexure directly, and that the high-thermal-conductivity member is inserted and fixed between the flexure and the load beam in the region containing at least a section on which the drive IC chip is to be or is mounted.
It is also preferred that the lead conductor member is formed by a FPC (flexible printed circuit) member, and that the high-thermal-conductivity member is inserted and fixed between the FPC member and the load beam in the region containing at least a section on which the drive IC chip is to be or is mounted.
It is further preferred that the lead conductor member has a section for mounting the drive IC chip, located at a middle of the suspension.
It is preferred that the suspension or the HGA further includes a base plate fixed to a base section of the load beam, and that the lead conductor member has a section near the base plate, for mounting the drive IC chip. In this case, preferably, the high-thermal-conductivity member is inserted and fixed between the base plate and the load beam in the region containing at least a section on which the drive IC chip is to be or is mounted.
It is also preferred that the high-thermal-conductivity member is a metal member made of a metal material containing one of Al, Cu, Mg, Al alloy, Cu alloy and Mg alloy.
According to the present invention, fu
Honda Takashi
Ota Norikazu
Shiraishi Masashi
Wada Takeshi
Armstrong, Kratz, Quintos Hanson & Brooks, LLP.
TDK Corporation
LandOfFree
Suspension, head gimbal assembly and manufacturing method of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Suspension, head gimbal assembly and manufacturing method of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Suspension, head gimbal assembly and manufacturing method of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3327981