What material systems do you use?

• Dupont 951 or Ferro A6S Material systems are in volume production. Other systems like Dupont 943, Dupont HTCE, Heraeus CT700, and Heraeus CT2000 etc. are under study and/or have been used.

How long have you been producing LTCC substrate in volume?

• We have been in LTCC field for more than 15 years, low volume for military and space for the last 15 years, medium to high volume for industry for the last 10 years, very high volume for handsets for the last 5 years.

What is your current installed capacity?

• We have two sites(one is located in France and the other is in Taiwan). The total volume production capacity is over 20 millions cm2 of fired layer per month with 6"x6" sheets & free-sintering process( 1.5 times more with Zero-Shrinkage process; 1.75~2 times more with 8"x8" green sheet ).

What standard panel sizes do you use for production ( 6"x6", 8"x8", 10"x10", other?)

• 6"x6" in volume now, 8"x8" will ramp up for volume production from 2nd half this year, Y2003. All of our equipments in our facilities are designed as compatible up to 10"x10".

What is your standard lead time for prototype sample delivery?

• Typical 2 weeks, one week could be achievable based on circuit and construction complexity.

Where are the locations of your production facilities?

• Tainan/Taiwan and Argentre/France. But Taiwan will be major volume manufacturing site eventually.

Can you provide a design guide?

• 2 first chapters of our design guides which describe in details the services and the technologies we offer, could be free downloaded from our website. The chapter about our design rules to guide your layout design will be available once signing up mutural NDA. Some libraries and engineering support will be also available to speed up your design cycle. Please contact us for details.

What is your major market segment? for example, aerospace, telecommunications, medical, automotive and military?

• Our segment is the high volume foundry (Handsets, Automotive) and that we also manufacture substrates in medium quantities for industry (Medical, Telecoms) and in small volume (Military, Aerospace).

Are you a subsidiary of a larger company, publicly held or private company?

• We are a joint venture of Darfon Electronics Corp. and Thales Microelectronics Corp. Darfon is an affiliated company in BenQ Group who is a global leader in multimedia and communications products and computer peripherals fileds. BenQ Group generated 3.3 billion US dollars revenues in 2001. Thales Microelectronic is an affiliated company in Thales Group who is a global electronics company serving Aerospace, Defence, and Information Technology markets worldwide. With operations in more than 30 countries and 65,000 employees, the Thales Group generated 10.3 billion euros revenues in 2001. DT is not publicly held company yet now.

Who are your customers?

• We are working with several worldclass clients of solution providers in the major wireless communications fields like Bluetooth, WLAN, Cellular applications. We are sorry that we can't disclose our client information under NDA governance.

What is your tape thickness?

• We can provide the various range from 20um up to 200um tape thickness.

What is your layer to layer alignment tolerance?

• Down to +/- 30um.

What is lowest line/space you can currently achieve in volume production?

• Down to 75/75um.

What is lowest via pitch you can currently achieve in volume production?

• Down to 200um

Could you provide substrate with the castellation and cavity design?

• Yes, we can provide this kind of substrate but we don't currently recommend design with two sided cavities. We have our own process technology to control the flatness of cavity. For detailed specification, pls refer our design guide chapter 4 or contact with us.

What kind of I/O styles you can do?

• The most usual I/O styles included:
  BGA(Ball Grid Array)
  PGA(Pin Grid Array)
  LGA(Land Grid Array)
  Clip leads(J leads, L leads or G leads)
  Castellation
  LGA with side

What kind of passive components could be embedded? What component value and tolerance could be achieved? and if saw filter or active components can be embedded as well?

• Capacitor and Inductor could be buried inside layers. Resistor is not still recommended to bury inside but could be printed on our substrate surface. Besides, the integrated LC function circuits could be buried inside as well, something like coupler diplexer, LPF BPF balun, etc..
• Buried Cap could reach 100pF, min5% tol, Buried inductor could reach 60nH, min 5% tol for general application. The Cap Value will depend upon the layer thickness and the available layer q'ty and space in your design, the typical capacitance value per mm2 per ceramic layer as below for your design reference.
  
• Active component(SAW, die or diode) still could not been buried inside layers. But, we can put as surface mounted or wire-bonding, flipchip packaged into our substrate. Cavity is also feasible if your design has height limitation.

Any LTCC specification benefit than FR4?

• Hi Q / Low loss, Precisely defined properties, Circuit density, Integral components, Functional trimming, Environmental stability, TCE match to Si/GaAs/SiGe, Thermal performance, Mixed Analog/Digital/RF, Integral Hermetic Packaging, Volume Manufacture
  

• Low Temperature Co-fired Ceramic (LTCC) technology is a multi-layer ceramic process that can be used to fabricate low cost, high performance RF and microwave components. It is an extremely versatile technology that can be used to realize a wide range of components from simple passive filter structures and packages to complex sub-system assemblies containing discrete SMT (Surface Mount Technology) components, bare die and printed passives. This description of the LTCC process makes it sound similar to conventional multi-layer circuit boards fabricated using laminate materials such as FR4. However, LTCC has a number of advantages:
  •Lower loss dielectric (lower tanδ)
  •Better controlled dielectric properties (εr, tanδ and thickness)
  • It is well suited to producing modules in low-cost SMT packages, including BGA topologies
  •LTCC processes can produce modules, which are well suited to incorporating bare die. Cavities and integral heat-sinks can be easily released
  •Many processes allow the integration of printed passive components (resistors, capacitors and inductors)

T.C.E. comparison between Ceramic,FR4 and Silicon?

• LTCC:2.5~8(ppm/℃, 40-400℃), FR4:13 (ppm/℃), Si:(3.6ppm/℃).

• LTCC:3~5(W/m,25℃), FR4:0.25(W/m,25℃).

What is the difference between HTCC and LTCC technology?

• LTCC can be defined as a multilayer circuit fabricated by laminating single green sheets (term for unfired tapes; Green Tape, Dupont) with printed conductor lines etc. on the surface on top of each other and firing them all together in one step. This process is almost similar to that of HTCC, but the big advantage of the LTCC system is the possibility to use low resistivity conductors like silver, gold, copper and alloys with palladium and platinum instead of tungsten and molybdenum; the separation between this two (different) technologies is defined with the firing temperature: in excess of 1000°C for HTCC and below for LTCC (mostly 850 to 875°C, what makes it possible to use silver for conductor lines etc.). The whole process includes several steps that are described under "LTCC Process".
  The LTCC technology avoids many disadvantages the others have and offers a couple of benefits:
  Economizes multiple steps of the manufacture process compared with the conventional thick film technology (parallel processing); Mass production methods can be really applied (several processing steps can be automated); Fabrication techniques are relatively simple and inexpensive; Tapes of different compositions can be manufactured with desired layer properties; Thermo-physical properties can be modified; Possibility of auto-packaged devices fabrication; Electronic circuits can be integrated, using its hybrid nature; Design and manufacture 3-dimensional circuits; Possibility of cutting the tape / substrate into different shapes; Because of the possibility to bury passive components within the substrate, it reduces the size of circuits (down to about 50 percent in comparison to the PCB); Number of signal layers almost unlimited; Ability to perform at frequencies over 30GHz; High resistance against ambient working temperatures (up to 350°C); Good thermal conductivity compared to PCBs (factor 10); Good match to semiconductor TCEs; Very good hermeticity of the substrate.