EPTE Newsletter from DKN Research 
#820, June 22, 2008
(www.dknresearch.com)
Topics of the Week
JPCA Show 2008  (Part II)
The hot item at the convention this year was embedded components in the 
multilayer boards and flexible circuits.  It seems to be a very 
?fashionable? trend that started last year, and most of the major rigid 
board companies and flexible circuit manufacturers paraded their latest 
achievements from their technological departments.  Material suppliers and 
machine manufacturers also threw their hats in the ring featuring some 
sales pitches that involved embedded components. 
There are two basic technologies used for embedded components. The first 
is forming passive components by screen-printing or photolithography 
inside or outside of the circuit boards.  The concept is not very new, and 
the technology came to light and really took off several years ago at the 
IPC Expo in the U.S.  The basic idea has not changed; however it has 
evolved and the accuracies and value of the passive components have become 
much larger.  Mitsui Metal Smelting released 8 microns thick dielectric 
layers for Farady Flex and Fujikura Kasei announced that 50 are available 
as the dielectric constant of the screen printable ink.  For circuit 
manufacturers it allows them to form larger capacitances in the same 
spaces on the substrates compared with traditional materials.  Asahi 
Chemical Laboratory provides several carbon conductor inks for embedded 
resistors. These carbon inks cover 5 orders of resistors 100 ohms to 10 
mega ohms in small spaces by the screen printing processes.
The second basic technology used for embedded components involves mounting 
the chip components inside the multi-layer boards.  During the early 
stages of the development process for the technology, actual chip devices 
for passive components were introduced. Today major circuit board 
manufacturers are trying to use semiconductor chips as the embedded 
components. Thin semiconductor chips are mounted in small cavities already 
prepared inside the multilayer boards. Because the wire-bonding technology 
has physical difficulties when covered by the other circuit layers, 
manufacturers began experimenting with new connection technologies. The 
flip-chip process is probably the most common technology used to make the 
connections for mounted chips. Toray Engineering, a major equipment 
supplier for the circuit board and assembling industry, launched new lines 
of flip chip bonding machines for both rigid substrates and thin flexible 
substrates. The automated bonding machines pick up the small thin chips 
from trays or diced wafers for large size circuit boards.  One manager 
from Toray engineering told me they are selling a lot of flip chip bonding 
machines to new customers from circuit board companies, flex circuit 
manufacturers and OEM assembling companies.  Toray Engineering 
representatives speculate these new customers use the machines for 
embedded semiconductor chips. 
I surveyed major rigid board manufacturers and flex circuit manufacturers 
inquiring about the latest progress with the embedded component 
technologies. Most manufacturers spoke about the advantages of their 
technologies, but few could provide clear answers relative to the 
reliabilities and actual production volumes.  DNP, one of the major 
circuit board manufacturers in Japan, was the only company that provided 
actual samples of the circuit modules with embedded semiconductor chips. 
DNP representatives who worked the booth stated that they ship millions of 
embedded modules every month to a European cellular phone manufacturer.
I came away from the exhibition feeling that embedded components are still 
in the R&D stage. Both circuit board manufacturers and their customers are 
wondering whether embedded components will be part of the industry main 
stream and if this technology is adopted what is the major process for the 
technology.
Dominique K. Numakura
DKN Research, www.dknresearch.com