Site: Hitachi PERL and HIMEL
292 Yoshida-cho, Totsuka-ku
Yokohama-shi
Kanegawa-ken 244, Japan

Date Visited: October 6, 1993

Report Author: L. Salmon

ATTENDEES

JTEC:

P. Barela
J. Kukowski
L. Salmon
R. Tummala

HOSTS:

Dr. Hiroyoshi Matsumura
Mr. Ikuo Kawaguchi
Mr. Toshiro Kinugasa
Mr. Ryugi Nishimura
Mr. Masahiko Yatsu
Dr. Norikazu Tsumita
Dr. Toshio Asano
Mr. Takanori Ninomiya
Dr. Hisashi Sugiyama
Dr. Makoto Iida

BACKGROUND

Hitachi has nine corporate research laboratories with approximately 5,700 employees. The corporation spends approximately $3 billion per year on research and development. This amount corresponds to approximately 10.5% of total sales for the company. The first corporate R&D laboratory, the Central Research Laboratory, was established in 1952. We visited two of the corporate research laboratories, the Production Engineering Research Laboratory (PERL) and the Hitachi Image and Media Systems Laboratory (HIMEL), which are both situated at the Yokohama site together with the Systems Development Laboratory.

PERL is a corporate research laboratory and has as its major goal research in the areas of advanced packaging, precision machining, factory automation, high-density magnetic media, and advanced semiconductor materials and processing. The laboratory has approximately 600 employees and was established in 1971.

HIMEL is also a corporate research laboratory and is chartered to perform research in technology areas of importance to camcorders and other optical consumer products. The laboratory has approximately 400 employees and was established in 1972. The laboratory was originally an associated division of the Consumer Products Group, but was designated as a separate research laboratory in February of 1993. Its purpose is to work closely with the production divisions to provide technology required for new products. HIMEL is divided by products into four departments: projection displays, range finder video cameras, LSI design and fine mechanism development, and fax/word processors.

Hitachi's philosophy regarding research is called Tokken and is based on tight coupling between production and R&D efforts. Connections between production and R&D groups include personnel exchange, common planning, and frequent meetings to assure coordination. The charter of each of the organizations in Hitachi is summarized in Table PERL.1. This chart is idealized and is not always rigidly followed. Research staff will sometimes work at the development facility for extended periods during technology transfer. In other cases, the development staff may come work at the research facility for an extended period.

Table PERL.1
Summary of Organizational Responsibilities

Mr. Kinugasa from HIMEL first gave a presentation on Hitachi's design and manufacture of camcorders. He began with presentation of a roadmap for reduction in camcorder size through integration of camcorder functions into fewer LSI and fewer discrete components. The path he outlined shows an evolutionary approach to reducing the number of components and does not hope for revolutionary changes in IC technology for at least the next four years. He projected continued use of hybrid and PCB technology to package the components and exploitation of shrinking feature sizes in IC technology. TAB and bare chip technology are not part of the current packaging plan because these technologies are more expensive to produce. Current PCBs are designed with a 0.5 mm pitch. Efforts are under way to decrease pitch size to 0.4 mm and 0.3 mm, and the technologies will be included in products if the cost is not too high. Hitachi is developing optical inspection techniques for 0.3 mm technology because x-ray inspection is blocked by the large number of metal layers on the PCB. Inspection for 0.3 mm is currently performed manually. The most advanced SMT process Hitachi has developed is 0.3 mm pitch on a six-layer PCB that is 1.6 mm thick. The solder paste screen is made using an Ni additive process. Super solder is not used because solder deposition was found to be too uneven.

Mr. Kinugasa indicated that packaging accounts for 20% of IC production cost, and he anticipates that the percentage cost will continue for new products. The major impediment to dramatic reduction in camcorder size is the size of the recording tape and associated mechanical parts required to read and write to the media. During a tour of HIMEL facilities, our hosts indicated that HIMEL is seeking to reduce discrete component size below the 1005 size part. They also indicated that the plan for HIMEL includes development of the technology required to build a pocket-size, all-solid-state camcorder. Our hosts suggested that some effort is being expended to investigate bare chip technology using conductive adhesives in order to address environmental concerns regarding lead-based solders.

The JTEC team was given a tour of the clean-room facility used to pursue research in the areas of advanced disk drive media and thin film MCM development. The facility is approximately 10,000 sq. ft. and is class 100/1,000. PERL is also investigating high-density magnetic media and advanced thin diamond-like coatings to protect hard disk media. Research on magnetoresistive magnetic storage is carried out at a separate Hitachi laboratory.

The thin-film-on-ceramic MCM process is being pursued to support high-performance supercomputer applications. The technology provides excellent thermal properties and is designed to dissipate heat from high-power ICs. Dr. Inoue indicated that the technology will be used for the next generation of high-end supercomputer, but that it is unclear what technology will be used for packaging for the generation after that. He stated that thin-film MCM technology may be important for workstations, but that the cost of the process will have to be decreased significantly before the technology can be used in that area. Current research efforts are concentrating on cost reduction in the process, but there are no immediate plans to use the technology in Hitachi workstations. We were told that this technology would not be used for consumer applications due to its high cost.

We were given a tour of the facilities for several projects at PERL. There is a strong effort to develop the technology and equipment required to automatically inspect and evaluate the quality of products and processes. Successful equipment and techniques developed in the laboratory are immediately implemented in the manufacturing line. PERL makes extensive use of image processing to decrease highly accurate inspection of high-definition CRT screens. PERL is also active in developing systems to automatically inspect green sheets for multilayer ceramic packaging and solder quality in SMT reflow processes.

Scientists at PERL have developed an advanced PCB that they call TAF-II. The process uses an additive metalization process that results in improved resolution: line widths as small as 140 microns in 35-micron-thick copper. The process flow for the TAF-II process is shown in Figure PERL.1. The lamination, drilling, and catalyzation steps are similar to those in standard PCB processes, but the following steps differ from standard processes: Solder resist is formed through an etched stencil; the plating process is an electroless plating step in a bath with a pH of 12. The PCB typically contains 4-6 layers, but the PERL researcher claimed that the process would support as many as 12 layers. He also claimed that the TAF-II process is 20% less expensive than the standard PCB process because less plating solution is used in the selective plating process. The TAF-II process was licensed to several companies in 1989, and a new process, TAF-III is in development. TAF-III will use lithography to define the solder resist layer and will have line widths as small as 80 microns.


Figure PERL.1. Brief process flow.

Dr. Makoto Iida presented work on thin molded plastics for laptop computer cases. He showed research on methods to reduce the thickness and mass of the plastic required for a domestic Japanese portable PC product, describing a roadmap for thinning body plastic thickness from 3 mm in 1985 to 1.5 mm in 1993. PERL researchers are currently working to reduce the size of the plastic case by improving structural design of the case, the polymer material used in the case, and mold design. Hitachi has developed its own polymeric material, together with an associated company. One of the greatest challenges is to control flow of the resin during filling of the mold. PERL researchers have analyzed resin flow using a simulation program to predict the best method to inject resin into thin molds. Dr. Iida stated that although composite materials can be made thinner, they are only used in higher-value products such as computer pen pads, due to the high cost of the material. Composite materials can be molded as thin as 1 mm and weigh less than conventional plastics. Overall thickness of the portable product was also reduced by using the LCD display as a structural member. A shock-absorbing material was used to assure that LCD reliability remained high. Dr. Iida indicated that PERL is investigating molded circuit boards, but present cost of materials is very high. He indicated that the thermal expansion characteristics of the molded circuit board material are very important.

Dr. Iida then described a rework tool that has been developed to add or remove solder from SMT parts with a pitch as small as 0.3 mm. The tool removes excess solder using a braided wick, and adds solder using a novel technique. A droplet of solder is held by surface tension to the end of a heated point and the solder is placed on the unsoldered joint. The solder and the lead are heated in a single step.

There were several general comments made during the JTEC visit to Hitachi that are worthy of note. First, although a high level of automation is evident in the production philosophy of Hitachi, individuals at PERL emphasized the importance of an "appropriate" level of automation. They stressed that overdependence on automation is as detrimental as underdependence on automation. They further stressed the importance of the skilled individual to improve production yield and to retain production flexibility. The managers at PERL indicated that process floor workers should have a college education. When asked, they agreed that it is difficult to attract high-caliber people to production tasks, but indicated that showing employees the importance of their contribution to production is the best method to attract them.

A second theme was the importance of cost in all decisions regarding technology. Cost was clearly a critical consideration in every discussion regarding proposed technology. There was always a clear product path, and the cost of a technology was compared to a projected, required production cost. One statement made by Dr. Matsumura summarized this attitude. He said, "We used to determine the price of a product by adding an acceptable profit margin to the projected cost to produce a product. Now the price is a predetermined quantity, and we add an acceptable profit margin to arrive at the required product cost."


Published: February 1995; WTEC Hyper-Librarian