Cost
SAYFU is one of the largest PCB fabricators in China, and is regularly in the top 5 in terms of heavy copper material usage, We have a history of producing heavy copper PCBs for automotive and commercial applications. As a result, we are able to negotiate some of the most favorable materials pricing in the industry.
From a processing standpoint, we have optimized our processes through the installation of new etching and lamination lines that are ideal for etching and pressing heavy copper PCB’s without severe impact to productivity and throughput.
Delamination
Throughout the years, we have tested and perfected stackups and calculators that are instrumental in helping us to achieve the best of both worlds – keeping within the maximum thickness allowance while still pressing with enough resin to fill all voids. Furthermore, our lamination presses use hot oil platens to ensure heat is applied uniformly across the entire production panel. This helps to guarantee and even cure across the panel, which is key to avoiding delamination.
Inner Layer Alignment
Generally, heavy copper PCB’s are produced using thin core materials. Thin core materials are known to require varying degrees of scale factors to account for material shrinkage during lamination. Heavy copper PCB’s are more prone to alignment issues that manifest themselves in the form of exposed copper in cutouts for windings and along the edges of the PCBs. This is due in part to the larger window of etch factor that is common for heavy copper PCBs.
We have avoided this issue in large part to studying varying core materials in combination with copper retention percentages. A key instrument in these studies is the use of the PerfecTest system and resulting knowledge database. We consult this database each time a new part number is produced.
As a result of our extensive experience with Heavy Copper PCBs, we have achieved UL certification of up to 6 ounce copper for inner and outer layers. For non-UL requirements, we have produced up to 20 ounce copper PCBs!
Etching
One part of the fluid dynamics of the etching process is called “puddling”. Since etching is a horizontal process, etching chemistry is sprayed on to the top and bottom of the panel. While the chemistry that is sprayed from the bottom falls back off the panel, the chemistry sprayed from the top remains on the panel, forming a puddle. This puddle then absorbs much of the force of the newly sprayed chemistry. Since etching is as much a function of the physical force of the chemistry hitting the copper as it is a chemical reaction, the etch rate on the top side of the panel is reduced. This requires the operator to slow down the line speed in order to properly etch the top surface. As a result, the bottom side is often over-etched.
SAYFU has recently installed Hollmuller etching lines for both inner and outer layers. These lines have the latest anti-puddling spray technology incorporated within them. This technology uses a specific spray pattern and nozzle arrangement, along with an oscillating spray bar, to “sweep” away old etchant so that newly sprayed etchant is sprayed directly on to the copper surface. Furthermore, these lines automatically control temperature and chemistry concentrations to insure uniformity throughout the production process.
China PCB manufacturer SAYFU Technology production type 产 品 类 型
■高频印制板（ＨＦＰＣＢ）：适用微波传输电子产品
High frequency PCB(HFPCB):suitable for electric products
with microwave transmission
■双面印制板（DPCB）：基材FR4
Double-sided PCB(DPCB):with base material of FR4
■多层印制板(MPCB)：基材FR4、PP
Multi-layer PCB(MPCB):with base material of FR4 and PP
■高密度印制板（HDIPCB）：含埋/盲孔，适用BGA电子产品
High-density PCB(HDIPCB):including built-in/blind holes,
which is suitable for BGA electric products
■铝基印制板：贝格斯铝基板，适用大功率散热电子产品
Bergquist Aluminum based board:suitable for electric products with high power heat dissipation
■多层盲孔板：适用仪器电子产品
High and multilayer printed circuit board with blind&buried via boards:suitable for instrument electric product
■厚铜板（3-10 Oz）和厚金板：适用电源产品
Heavy copper boards (3-10 Oz) and heavy gold board:suitable for power printed circuit board product
■软硬结合板：适用电脑、工业控制产品
Rigid-flex or Flex-rigid boards:suitable for computer and industry control products.
■软板(柔性线路板)：适用电脑、工业控制产品
Flexible printed circuit boards (FPCB):suitable for computer and industry control products.
(Note: China PCB manufacturer SAYFU Technology specially produces on rigid printed circuit board; printed wiring board; mulitlayer printed circuit board; flex-rigid printed board, rigid-flex printed board; metal core printed board; heavy copper coard; power board; heavy gold board; Flexible board/Flex PCB; Bergquist Aluminum based board/Al PCB; Metal Core PCB; PCB/PWB/FPCB/FPC/MPCB/Rigid-Flex PCB)
SAYFU Contact way:
Tel#+86-755-26417916
Fax#+86-755-26417917
sales@sayfupcb.com
sales1@sayfupcb.com
www.sayfupcb.com
