Breaking News from SEMICON West | 3D InCites

Breaking News from SEMICON West | 3D InCites

Optosem Technologies Sdn Bhd's Notes

• Cavity Packages Explained
  Plastic Cavity Packages (PCP) is not new as have been around since Optical Mouse days. Available traditionally in PDIP and SOIC,  the PCP have also been used for pressure sensors . Both packages are still very much  running in volume today. The development of cavity QFN and DFN (ACQFN) opens up newer application for RF, Photonics, MOST and other mid frequency (upto 4.5 GHz) fiber optical application. Engineering qualification and Pre production trial is ongoing in Optosem for use in  MEMS Gyro, and Timing chip. Air inside cavity packages is preferred media for some application for improved performances.  

  
  

  PCP used for premold packages, are requires to meet 3x solder reflow, similar to mainstream semiconductor, plus others requirements  (RoHS, HF,Reach etc). LCP , a very high temperature thermoplastic is preferred engineering plastic  and which meets these requirements. LCP  strength besides high heat resistance are its good flow, mechanical strength, wide processing window , and is green (can be recycled). Preplated lead frame like NiPdAu is also plating choice, which eliminate need for wet process at component level. NIPdAu PPF is also a common finishing  process for mainstream IC , and thus meets solder wetting requirement  similar to IC semiconductor.

  
  

  PCP, ACQFN are lower cost package solution to use of LCC and Laminates for MEMS. It offers better matched CTE to die, and for peripheral products are well suited.

  
  

  

  Punched Cavity QFN (ACPQFN)

  
  

  

  High Density PDIP Cavity Packages (PCP) 

  
  

  

  MAP DFN (ACMDFN)

  
  

  

  Punched Cavity QFN (ACPQFN)

  
  

  

  5x5 ACMQFN

  
  

  

  PCB Cavity Packages 

  
  

  

  Cavity QFP (ACQFP) 

  Optosem runs millions a month cavity packages, serving customers in both consumer, automotive  and communication sectors. Our smallest packages is 2.10mm x 3.50mm DFN.  We have the expertise to support packages design, and assist with assembly process setup. Our vertically integrated  operation includes in house tooling design and fabrication, and our strong partnership with very key and substantive lead frame suppliers.