STABLCOR Frequently Asked Questions

Transcription

1 Q.1 What is STABLCOR? STABLCOR is a laminate based thermal management technology for the Printed Circuit Board and Substrate markets. Q.2 What are the benefits of using STABLCOR Technology? There are FOUR main benefits of using STABLCOR technology. 1. Thermal Conductivity: Ideal for Conduction cooling and reducing Hot Spots on the PCB 2. CTE (Co-efficient of Thermal Expansion): Allows you to tailor PCB CTE to match with Ceramic or Flip Chip type packages. Reduces CTE mismatch and increases Solder Joint Reliability (SJR) 3. Rigidity/Stiffness: Allows eliminating metal reinforcement and stiffeners. Increases Rigidity without adding weight, thus increasing shock and vibration reliability 4. Weight / Density: As light weight as typical glass fiber composite material. Density 1.75 g/cc. Q.3 What is STABLCOR Laminate? STABLCOR laminate is a thermally and electrically conductive carbon composite material. Q.4 Is STABLCOR laminate a dielectric material? No, STABLCOR laminate is an electrically conductive material. Q.5 Can I replace dielectric material with STABLCOR material? No, you can not replace a dielectric layer with STABLCOR laminate. STABLCOR material replaces the copper plane layer. Q.6 What is the Glass Transition Temperature (Tg) of the STABLCOR material? We have two grades of material to support the Epoxy and Polyimide market. EP387 Epoxy STABLCOR material has Tg=170 o C and LC909 Polyimide STABLCOR material has Tg=240 o C. Q.7 What is the standard thickness of STABLCOR material? We have two types of the STABLCOR laminate materials, ST10 and ST325. ST10 material has 4.5mil, 6mil, 9mil and 18mil core thicknesses. ST325 material has 8mil core thickness. Copper is not included in these thicknesses. Q.8 Does STABLCOR laminate have copper on one side or both sides? STABLCOR laminate has copper on both sides Q.9 What are the standard copper thicknesses available? Half ounce and one ounce copper on both sides is typical. Thicker copper may be available upon request. Q.10 What is the standard panel size for STABLCOR laminate? Standard panel size available today is 18 x24 (457mm X 609mm). Custom sizes may be available upon request. Q.11 What is the largest panel size of STABLCOR material available? Material is produced in 36 x48 (914mm X 1219mm) sheet. Q.12 Can I buy STABLCOR material? Normally, if you are not one of the licensed fabricator you can not buy STABLCOR material. But, you can request sample material for evaluation or you can buy STABLCOR printed circuit boards from licensed fabricators. Q.13 Where can I find list of the licensed fabricators? You can find latest list of licensed fabricators on our website at Q.14 Is STABLCOR material tested for flammability? Yes. It is tested and rated to flammability V-0 rating Q.15 Do you have a data sheet for STABLCOR material? Yes. It is posted on our website under technology page. 1

2 Q.16 Since the STABLCOR composite has copper on both sides and the composite is not a dielectric material can both copper layers be used as a different plane or circuit layer? No. The whole STABLCOR laminate (Cu STABLCOR composite Cu) will be used as only one plane layer in the PCB stack-up. Q.17 Can I use STABLCOR material as a signal layer? No, STABLCOR laminate can be used only as a plane layer, preferably a GROUND plane layer Q.18 Can I use STABLCOR material as a Power layer? Yes, you can use STABLCOR laminate as a power layer but it is not recommended. You may run a risk of having STABLCOR material exposed along the edges of the printed circuit board. Care must be taken to protect the edges from a potential short circuit. It requires additional processing steps at PCB manufacturing level which also leads to low yield. Thus, it will cost you more. Q.19 Can I use STABLCOR material as a split plane? Yes, you can use STABLCOR material as a split plane but it is not recommended. Split plane can not create an Island within a plane area. Split plane can be used as a Peninsula type or as long as both ends of the split plane line comes to the edges of the PCB. It requires additional processing steps at PCB manufacturing level which also leads to low yield. Thus, it will cost you more. Q.20 Do I have to replace all plane layers with STABLCOR material in a design? No, you don t have to replace all plane layers with a STABLCOR material. Only selected number of plane layers needs to be replaced with STABLCOR material, typically 2 nd layer from the outer layers. Two layers of STABLCOR material next to the surface layers are the most common structure used. Q.21 Is the whole PCB or Substrate made using STABLCOR material? No, you can not make all the layers of a design using STABLCOR material because it is an electrically conductive laminate. STABLCOR material is used only to replace some of the plane layers, preferably the Ground plane layers Q.22 Can I use standard FR4 dielectric with STABLCOR material? Absolutely you can. You would use EP387 grade of STABLCOR material with FR4 dielectric. Q.23 Can I use Polyimide dielectric with STABLCOR material? Absolutely you can. You would use LC909 grade of STABLCOR material with Polyimide dielectric. It is highly recommended to use low temperature cure polyimide prepregs (cure temp. <400 o F) with LC909 product. Q.24 Can I use STABLCOR material if I have mix dielectric materials in a design? Yes you can as long as you have a minimum two ply of 106 prepreg on both sides of the STABLCOR layers to fill pre-drilled patterns with dielectric resin. Q.25 Do I need special dielectric to bond STABLCOR material with the rest of the layers? No, you can use standard off-the-shelf prepreg to bond STABLCOR materials with the rest of the layers. It is recommended to use minimum 2ply of 106 prepreg or equivalent on both sides of the STABLCOR laminate. 106 prepreg is thinner and have higher resin content to fill and bond STABLCOR material within the PCB stack-up. Q.26 Can STABLCOR be used with blind buried via technology designs? Absolutely you can. You need to make sure STABLCOR layers are symmetrical into each sub-assembly and final lamination stack-up. Q.27 Can STABLCOR be used with laser micro via technology? Yes. STABLCOR material is compatible with laser drilling process. Q.28 Can STABLCOR material be used for Build-up Substrate application? Yes 2

3 Q.29 What is the cost premium between a STABLCOR/Epoxy board and a Standard FR4 board? It depends on the complexity of the design. If the design is high tech then the premium to incorporate STABLCOR would be less. If the design is very simple, the cost delta would be higher to add STABLCOR. Speaking very general, to add STABLCOR to FR4 design the premium would range from 40% to 200% Q.30 Can our current board supplier build STABLCOR boards for us? STABLCOR boards can only be manufactured by a licensed PCB manufacturer. You can find a list of authorized fabricators on our website ( If your current board supplier is listed on our authorized fabricator list then they can build STABLCOR boards for you. Q.31 Does PCB or Substrate manufacturers need to invest in any equipment to process STABLCOR? No. If one can manufacture multilayer PCB or a Substrate using existing equipment, the same can be used to manufacture STABLCOR PCBs. Q.32 If my current board supplier is not listed on your approved list, how do I get them on your approved list? Have your preferred fabricator contact us and we will walk them through a simple steps of how to get on our approved fabricator list Q.33 Can I Implement STABLCOR technology into my existing design? Absolutely you can. If you don t know how then let us look at your design (engineering@stablcor.com) and we can recommend the best way to use STABLCOR for your design Q.34 I am completely new to this technology, how do I use STABLCOR into my existing design? Contact us or send us your design at engineering@stablcor.com and our experienced engineers will assist you in walking through the steps to accomplish your goal. Q.35 Dose STABLCOR material affect impedance values of a design? Since STABLCOR material is used as a plane layer, it does not affect impedance values as long as there is proper dielectric material between the signal layer and the STABLCOR layer. Q.36 Why should I use STABLCOR technology? If you have thermal problems, hot spots, solder joint failure because of CTE mismatch, need more Rigidity without adding weight, then STABLCOR technology is ideal for you to use. Q.37 Why should I consider using STABLCOR material in my design? If you want to do thermal management without adding additional weight and also want to increase rigidity, this is the only solution that can do that. Q.38 I have a design that requires conduction cooling only. Can I use STABLCOR? Absolutely. STABLCOR technology is ideal for the conduction cooling method because it has quite a high in-plane thermal conductivity than through plane. Thus, STABLCOR acts as a built-in heat spreader and moves heat away from a hot spot quickly to the colder area of the PCB. Also, STABLCOR material is located very close to the surfaces of the PCB, thus a very short thermal path from the heat source to the STABLCOR material. STABLCOR material enables heat to move from the heat source to the nearest located STABLCOR layer and from there to the frame or chassis via a wedge lock or mounting means. Q.39 My design depends on forced air convection cooling, Can STABLCOR be useful? Absolutely. STABLCOR material has quite a high in-plane thermal conductivity than through plane. Thus, STABLCOR layers acts as a built-in heat spreader and moves heat away from a hot spot quickly to the colder area of the PCB. Also, STABLCOR material is located very close to the surfaces of the PCB, thus a very short thermal path from the heat source to the STABLCOR material. Basically, the entire STABLCOR PCB becomes a heat spreader with uniform temperature and thus any moving air can remove heat very efficiently from the entire PCB, enabling efficient forced-air convection cooling. The larger the PCB surface area, the better cooling effect you can get under similar air flow. Q.40 How can I simulate thermal performance of the STABLCOR material in my design? STABLCOR material is listed in THREE industry leading thermal simulation software. (1) TAS PCB from Ansys Inc., (2) FLOTHERM form Flomerics and (3) ICEPAK from Fluent Inc. You can select the type of STABLCOR material along with the right amount of copper and run a simulation. 3

4 Q.41 How do I get desired CTE of a design? You can tailor the surface CTE (in-plane) of a PCB by selecting the right type, the right thickness and the right location of the STABLCOR material within the PCB stack-up Q.42 If I have a Ceramic BGA and it requires PCB CTE of 6-8ppm/C, Can I use STABLCOR to closely match CTE? Yes, by putting the right amount of STABLCOR material at the proper location within the PCB stack-up you can achieve CTE 8-10ppm/C to closely match with CBGA. Q.43 If I want to mount a Flip Chip (CTE 2-4ppm/C) directly on a PCB, Can STABLCOR material enables such low CTE? Yes, by putting the right amount of STABLCOR material at the proper location within the PCB stack-up you can achieve CTE 2-4ppm/C to match with the Flip Chip Q.44 If my entire PCB is made using an epoxy THERMOUNT material to control CTE, can I use STABLCOR material with regular dielectric material to achieve the same CTE? Absolutely you can replace Thermount design with STABLCOR. You can use two to three layers of EP387 grade STABLCOR material with standard epoxy material to achieve the same CTE that you have achieved by non-woven Aramid material. Q.45 If my entire PCB is made using a polyimide THERMOUNT material to control CTE, can I use STABLCOR material with regular dielectric material to achieve similar CTE? Absolutely you can replace Thermount design with STABLCOR. You can use two to three layers of LC909 grade STABLCOR material with standard polyimide material to achieve similar CTE that you have achieved by non-woven Aramid material. It is highly recommended to use low temperature cure polyimide prepregs (cure temp. <400 o F) with the LC909 product. Q.46 Thermount material has a high through-plane CTE (Z-axis), does STABLCOR material also have a high throughplane CTE? STABLCOR material does not have a high through-plane CTE as Thermount has. Through-plane CTE of the STABLCOR material is only 45-55ppm/C where as through-plane CTE of the Thermount material is ppm/C (more than double). Just to compare, standard Epoxy and Polyimide material have a through-plane CTE in a range of 50-60ppm/C. Q.47 If my PCB is made using woven Kevlar material to control CTE, can I use STABLCOR material with regular dielectric material to achieve similar CTE? Yes, you can use two to three layers of STABLCOR material with standard dielectric material to achieve a similar CTE that you have achieved by woven Kevlar material. Q.48 Have you done a comparison CTE test between Thermount PCB and STABLCOR PCB? What is the result? Yes we have. We have tested a 14-layer PCB made from 85NT Thermount PCB and also tested a 14-layer epoxy board that had only TWO layers of ST10-EP387 STABLCOR material at L2 and L13. In-plane CTE was in a range of ppm/C. In-plane CTE was within 1.0ppm/C between the two PCBs. Q.49 What is the lowest in-plane CTE we can achieve in a finished PCB using STABLCOR material? We have tested a finished PCB and it has shown 3.0ppm/C as the lowest in-plane CTE. Q.50 How can I get the best rigidity using STABLCOR material? You must use at least two layers of STABLCOR material within the PCB stack-up. These two layers must be located as far as possible from the neutral axis (center line) of the PCB stack-up. In other words, these two layers must be located very close to the surface layers within the PCB layer stack-up. For further detail, review Rigidity Guideline on the website. Q.51 How can I reduce or eliminate metal stiffeners in my design? By using proper material ratio (STABLCOR material to non-stablcor material) you can achieve equal or more rigidity at substantially less weight. Thus you can reduce or eliminate heavy metal stiffeners. Q.52 Can STABLCOR material increase rigidity without adding weight to the PCB? Yes, because carbon fiber has a very high tensile modulus at very a low density 4

5 Q.53 Since STABLCOR material is thermally conductive, does it affect the assembly process? Yes, Because of the thermally conductive nature of the STABLCOR material it is recommended to run a first article or a mole to find out the exact thermal mass and adjust the assembly profile accordingly to obtain the best assembly results. Each licensed fabricator should be marking each shipment to notify the same. 5