Shrinking lines, spaces and vias make LDI, laser drilling, inkjet and buried components the technologies to watch.
Download a PDF containing the 29 figures referenced in this article.
The annual JPCA Show was held for three days from June 11 to June 13. It was the 38th show since it started many years ago. The show was called “JPCA Show 2008/2008 Microelectronics Show/JISSO PROTEC 2008”. The show provided a special corner called “The Third Environmental Pavilion” to introduce environmentally friendly technologies and increase awareness of environmentally important matters.
At the “Second Leading Edge Electronics Pavilion,” attention was focused on car electronics, thin display and mobile devices that Japanese electronic industry boasts of, and various interesting examples of electronic packaging were shown.
The main theme of the show was “Navigation for the Next.”
The number of exhibitors decreased from 637 (2007) to 626, but the quality of exhibitors remained high. JPCA counted 124,749 visitors in total, down from 2007’s 131,355 visitors. The number of overseas visitors accounted for 7.2%. The overseas visitors were from China, S. Korea, Taiwan, Hong Kong, N. America, Europe, India and a few other countries. The author sensed that there were bit more American and European visitors than last year. Some pictures of the delegates can be seen in Figures 1, 2, 3, 4, 5 and 6.
There are so many subjects to cover, but as usual, it is not possible to cover every aspect of the show. The main focus will be on laser microvia technologies, laser direct imaging, buried components printed circuits, inkjet legend printer, and other newer technologies.
Business Conditions
The general consensus is that the PCB business conditions in Japan for the first six months of 2008 was difficult a resulting negative growth of 3% to 5% compared to the same period last year. Shipment of consumable materials started to improve during June and further improvement has been seen in the third quarter. However, the order-shipment of production equipment was poor in the first half of 2008 and continued to be down in the third quarter. Many potential buyers have postponed the investments until later this year. On the other hand, since more than 50% the equipment sold is sent to other parts of Asia, particularly to China, relatively poor business in Japan does not mean a total disaster for Japanese equipment manufacturers.
The JPCA assessment of the Japanese PCB industry based upon answers obtained from about 180 fabricators is still positive, but the average of these responses indicated there is only 1% growth. The July “recovery slope” does not appear to be as steep as seen last year. Most PCB fabricators interviewed gave the author the following thoughts, “The first half is gone, let’s forget about it and let’s hope we will see better business in the second half.” Well, everyone hopes this is true.
Buried Components PCB
There were dozen of PCB makers which exhibited samples of their versions of buried components PCBs. Dainippon Printing, CMK Corporation, Panasonic Electronic Devices (PED), Ibiden, Oki Printed Circuit (OPC), to name a few. Figures 7 and 8 show some examples.
According to a JPCA investigation, $25 million worth of buried components circuits were produced in 2007. In 2012 the amount is forecasted to grow to $75 million. This quantity is rather small considering the total Japanese PCB “domestic” production was $11 billion in 2007.
Engineers who are “mental thinkers” tend to be excited about such new technologies, claiming that there will be no room to place components on the surface of PCB as technology advances. The reality is that buried components PCB is still very expensive and will face problems associated with burying components inside circuit boards such as heat dissipation. The fabricators of such boards interviewed mentioned that buyers jumped at the new idea and “tried to see the temperature of water,” and found out that it was too hot (expensive). As miniaturization and integration of functions continue, there is still plenty of room to surface-mount components and at this time, it is still much cheaper to do so. The only strong incentive to adopt buried components PCB is to improve performance despite higher cost. Notwithstanding such sentiment, it is a technology to be watched. One thing that was noticed at this JPCA show is that a majority of passive buried components are chip components rather than “formed” components such as screened resistors.
Laser Direct Imaging (LDI)
LDI is the author’s current pet subject since he has observed this technology over the past 20 years. As in 2007, all five manufacturers, Orbotech, Hitachi Via Mechanics (HVM), ORC Mfg, Fuji Film and Dainippon Screen (DNS) exhibited their products at the show. (Figure 9, 10, 11, 12 and 13)
Recent emphasis has been on automated panel handling system as the usage begins to spread to mass production. It does seem that the era of LDI has finally arrived. Fuji Film exhibited a new model of IMPREX that has now real time registration capability. Last year, ORC Mfg., a manufacturer of fully automated contact exposure system, purchased Pentax’s LDI division.
This year, ADTEC Engineering, another manufacturer of fully automated contact exposure system, decided to collaborate with Fuji Film, which made even a stronger conviction for the future of LDI. From now on, ADTEC will fabricate IMPREX LDI systems of Fuji Film at its facility in northern Japan.
Fully automated DXP-3502 for PSR by ORC Mfg is priced at 210 million Yen or about $2 million at the current exchange rate. This is a lot more expensive than the ORC model for pattern imaging introduced last year at JPCA Show, priced at $1.4 million (catalog price, of course). Success of this model is yet to be seen because of high price.
Generally speaking, in Japan, Orbotech’s Paragon series are recognized as good machines for ordinary PCB exposure with lines spaces greater than 30 µm, capable of using ordinary dry film of sensitivity, 50 mj/cm2 or greater although it can be used with dry film of higher sensitivity.
HVM is recognized for fine line exposure, lines and spaces below 20 µm, standard today for IC substrate design rules. ORC and DNS use short-arc, high-pressure mercury lamps, which enable the models to be used in conjunction with low sensitivity dry film. These models are also good for exposure of liquid photoimageable solder resist, which normally requires 450 mj/cm2 energy. Fuji Film is noted by users as the fastest LDI system depending on the view of various users, but this author has no judgment.
At the time of JPCA Show, the cumulative, worldwide installations of LDI systems by various makers including trial installations are estimated to be about 320 units by Orbotech, 40-50 units by ORC, also 40-50 units by Hitachi and 25 units, each, by Fuji Film and DNS. DNS (Mercurex) is said to have installed more units for solder mask exposure. The total is between 460 and 470 units, about 150 more than the same time last year.
This author estimates that there are about 6,000 fully automated contact exposure machines used worldwide currently. Slightly more than 320 units were sold worldwide last year. The number of manually operated contact exposure machines used worldwide today is ten times more, or about 60,000. There is still a long way for LDI to catch up to contact exposure equipment. The adaptation of LDI systems for all imaging exposure needs will be at accelerated pace in the next few years.
The use of dry film for LDI in Japan doubled in the last year according to Asahi Kasei and Hitachi Chemical. The author estimates that the monthly usage of dry film for LDI systems is somewhere between 2,000,000 and 2,500,000 m2 worldwide, which is less than 3% of all dry film consumed monthly, but is increasing constantly as more LDI systems are adopted. LDI dry film with high sensitivity is still expensive. As the power of LDI is increased, LDI users are more interested in “cheaper version” of LDI dry film. Therefore, the emphasis by dry film makers is more on price reduction, which will also contribute to the accelerated proliferation of LDI systems.
Laser Drilling Machines
The only new thing about laser drilling machine is four-table system introduced by Hitachi Via Mechanics (HVM). HVM claims that its speed is 1.85 to 1.9 times faster than popular two-table system with floor space requirement of only 1.5 times than two-table system. Microvia board makers struggling with floor space restrictions seem to go for this model. The author was told that booking for this model has been stronger than expected. The model was shown during TPCA Show in October 2007. This is the first time HVM introduced it officially to Japanese audience. (Figures 14 and 15)
The sale of laser drilling machines peaked in 2006 with total estimated new installation was about 960 to 970 units. It calmed down considerably to less than 800 units since 2007 and 2008 shipment is expected to remain at the same level as 2007, maybe a bit more.
The big question today is when UV/YAG laser will be used for mass production of IC substrates (flip-chip). Today, the share of UV/YAG laser machines remains at best 20 percent of total against CO2 laser machines. The key for the future of UV/YAG laser drilling lies in the diameter of microvia hole. UV/YAG laser is preferred to CO2 once the hole size goes down to 50 µm or below. (Figure 16 and 17)
One quiet change that took place in the last few years is from ”large window systems” to “CO2 Copper Direct” drilling methods. Mitsubishi claims that more than 500 units of Mitsubishi CO2 laser drilling machines are being used to drill microvia holes directly through copper foil (Figure 18). Many surface treatment methods are used effectively to enable this drilling. There are several chemicals suppliers offering surface treatment solutions such as Atotech, MEC and MacDermid. HVM also claims that more than 30 of its customers are now using “CO2 Copper Direct” drilling although it is not known how many of HVM laser machines are used for this purpose.
In the beginning of CO2 Copper Direct drilling, copper foil had to be etched down to a thickness of 5 µm. As the power of laser has increased and users better understand the essence of this drilling method, 12 µm copper foil thicknesses can be tolerated with reasonable efficiency and quality of drilling.
When laser microvias started to be used in the manufacturing of microvia boards, the microvia structure was typically 1+4+1, in which total number of laser drilled holes was about 300,000 to 350,000 per square meter. Today, advanced microvia boards for high end cell phone handsets and other digital handy products have structure of 3+4+3 and 4+2+4, in which total number of laser holes ranges from 2,000,000 to 3,000,000 per square meter. In such case, the CO2 Copper Direct method for drilling holes is faster and these higher drilling speeds are quite handy.
It is this author’s estimate that the total amount of microvia boards manufactured in 2007 (motherboards and flip-chip substrates) amounted to $10.3 billion, of which Japanese made about $4.9 billion (about $770 million was made overseas). Therefore, Japanese companies manufactured about 48% of the world production volume. Taiwan and China made about $2 billion each and S. Korea about $1.4 billion. These four countries accounted for 98% of the world microvia product production in 2007.
Mechanical Drilling Machines
HVM and Schmol Maschinen from Germany exhibited “independent axis drive machines.” In case of Hitachi just a photograph was shown. Schmol started to sell into the toughest market for mechanical drilling machines, Japan.
The popularity of such machines indicates a strong trend toward high-mix, low volume production practices in Japan, which was once the Mecca of mass production methodologies. Japan’s overseas production was about $5.5 billion in 2007, almost all of which came from mass production. Hence, there is more reason to adopt independent axis drive, LDI and inkjet printers, to accommodate low volume, high-mix manufacturing.
Inkjet Printers
New System (Orbotech) and PRINTAR were absent from the show. Micro Craft (Figures 21 and 22) and Yokogawa exhibited their models. The author has only vague idea about the number of installations in Japan. Before and after the show, he visited a dozen PCB shops in Japan and saw several inkjet printers from both makers. Later, he learned that there are a few more suppliers of inkjet printers in Japan.
By linking its moving probe tester, Micro Craft claims that it can send data of various kinds from the tester to the inkjet printer such as cross-out marks on defective circuits on a pallet, automatic scaling and placement of bar code (numbering).
Currently, worldwide installation is estimated to be about 220 to 230 units and is increasing daily. During the tour of Japanese PCB fabricators, the author was told that although minor, there are two problems associated with inkjet printers for legend. Filling ‘relatively” large area requires a bit of adjustment and sometimes, adhesion of legend ink is weaker than desired depending on the surface condition of solder mask and the nature of ink used.
A few inkjet printer makers tried in Japan ten years ago in vain. Finally, however, inkjet printer business seems to have back as viable business like LDI.
Other Topics
TCM (Tokyo Kakoh-Ki) showed a model of “floating etcher,” in which panels are grabbed from two ends and then goes through the etching solution without touching the wheels.
Ishii Hyoki exhibited a double side scrubber suitable for very thin panel.
Unlike other PCB shows, with one exception of ELECTRONICA, the JPCA Show attracts many PCB fabricators that exhibit capabilities at the show. This year’s show was no exception. There were approximately 40 to 50 PCB makers present. Some of the sample products they exhibited are show in Figures 23, 24, 25, 26 and 27.
Roadmaps
We shall end this report with JISSO Technology Roadmaps, which show what Japanese electronics industry is thinking. As can be seen in Figure 28, 0.3 mm pitch CSPs are now in production. Line and spaces on these products are 50 µm. The IC substrate trends seen in Figure 29 show that in 2008, 80% of the production will be 30 µm lines and spaces, 15% will be 15 µm lines and space and 7% will be 7 µm lines and spaces. In 2012 these tolerance are expected to shrink to 80% at 20 µm, 15% at 7 µm and 5% at 5 µm.
Enabling technologies like laser direct imaging, laser drilling, inkjet and other fabrication advances will continue to be the hot technologies to watch in the coming years. PCD&F
Dr. Hayao Nakahara is president of NT Information and a recognized expert on the PCB industry. He can be reached at This email address is being protected from spambots. You need JavaScript enabled to view it..
