HDI and Advanced HDI

High Density Interconnects (HDI) are utilized to meet the market demand for complex designs in smaller form factors across the majority of market segments, (Wireless, Telecom, Military, Medical, Semiconductor, and Instrumentation). HDI includes the use of fine features or signal traces and spaces of 0.003” (75 µm) or less and laser-drilled blind or buried microvia technology. Microvias allow the use of micro-interconnects from one layer to another within a PCB utilizing a smaller pad diameter creating additional routing density or reducing form factor.

A microvia maintains a laser drilled diameter of (typically 0.006” (150µm), 0.005” (125µm), or 0.004” (100µm), which are optically aligned and require a pad diameter (typically 0.012” (300µm), 0.010” (250 µm), or 0.008” (200µm), allowing additional routing density. Microvias can be via-in-pad, offset, staggered or stacked, non-conductive filled and copper plated over the top or solid copper filled or plated. Microvias add value when routing out of fine pitch BGAs such as 0.8 mm pitch devices and below.

Additionally, microvias add value when routing out of a 0.5 mm pitch device where staggered microvias can be used, however, routing micro-BGAs such as 0.4 mm, 0.3 mm, or 0.25 mm pitch device, requires the use of Stacked MicroVias® using an inverted pyramid routing technique.

Viasystems maintains years of experience with HDI products and was a pioneer of second generation microvias or Stacked MicroVias (SMV®). SMV® Technology offers solid copper stacked microvias providing rout–out solutions for micro BGAs.

Viasystems developed and now offer an entire family of microvia technology solutions for your next generation products.

The list below shows Viasystem’s entire family of Microvia Technology.

Standard or First Generation Microvias

• Create routing density (eliminate through vias)
• Reduce layer count
• Enhance electrical characteristics
• Standard Microvias limited to layers 1 – 2 & 1 - 3

Stacked MicroVias (SMV®) or Second Generation Microvias

• Allows increased routing on multiple layers
• Provides routing solutions for next generation applications
  • 1 mm – 0.8 mm – 0.65 mm - 0.5 mm – 0.4 mm – 0.3 mm & 0.25 mm
• Provides solid copper plate eliminating potential solder voiding
• Provides a solid copper plate
• Improves Current Carrying Capability & Thermal Management
• Provides a Planar surface for BGA (Via-in-Pad)

• SMV®

Deep Microvias (DpMV™)

• Provide additional dielectric material & small geometry features.
• Improved Impedance performance
• Provides RF Microvia solutions
• Provides a solid copper plate
• Improves Current Carrying Capability & Thermal Management
• Provides a Planar surface for BGA (Via-in-Pad)

• DpMV™

Deep Stacked MicroVias (DpSMV™)

• Provides additional dielectric for RF applications
• Maintains small geometries on multiple layers
• Improved signal integrity
• Provides a solid copper plate
• Improves Current Carrying Capability & Thermal Management
• Provides a Planar surface for BGA (Via-in-Pad)

• DpSMV™