IC Substrate PCB
IC substrate provides a connection between the PCB and the IC packages which are built on a Printed Circuit Board. For example, it looks like HDI PCBs with surface mount components.
Types of IC Substrate PCB
Ball Grid Array IC Substrate
Ball grid array IC packages use over 300 pins and high-performance based IC. Most processor types are BGA which tend to heat up more. 2,4,6 Layers (2+2+2 stacked via)
Chip Scale IC Package
The chip-scale substrate IC is thin and it is used for low pin count which is compact. Smaller package is used in memory, Communication, and lightweight commercial products
Single Chip IC Package
It’s a small IC package with a single IC on it like memory devices, telecommunication products or IC packages with a lesser pin count.
Flip Chip IC Substrate
Flip chip substrates are used for the Flip chip and Chip scale substrate IC. This aids in heat dissipation with protection for the circuits and reduces signal interference.
The IC Substrate Manufacturing Process
Copper Pattern and Plating
The copper pattern that is required for the circuit is taken and film is deposited on the laminate. The plating of copper happens with high precision using a chemical process.
Solder Mask
The solder mask consists of an IC substrate that is printed by filling the holes that fill on the cap of copper plating. The thickness of the copper plating circuit should be maintained at less than 10 mm for a better and hassle-free process.
Surface Treatment
The most common surface finish is EMIG or ENEPIG of gold alloys for surface finish with proper conductivity and uniform thickness.
Production Test
IC substrate is tested for reliability and internal connectivity with quality inspection in the last stage. Testing methods can include reliable integrated testing with Gigs or End-of-line testers.
Industries We Serve:
Consumer Electronics
Military/Space
High Power Applications
Medical Devices
Telecommunications
Industrial Automation
Material Characteristics of IC Substrate PCBs
Multi-Chip Module IC Substrate
Multi-chip module is expensive to manufacture but it can be used as the substrate for many IC packages.
Rigid IC Substrate
Resins are used to manufacture these substrates, generally, epoxy is used to build them but there are a few other types like ABF (Ajinomoto Build-up film), BT (Bismaleimide Triazine) which has a coefficient of thermal expansion between 12 to 17 ppm per degree Celsius
Flex IC Substrate
The substrate is similar to the flex Printed Circuit Board substrate with polyamide resin or polyimide. The coefficient of thermal expansion ranges from 13 to 27 ppm/degree Celsius which gives better performance and thermal management.
Design Considerations for IC Substrate PCB
IC substrates are made up of different electrical, mechanical, and chemical properties. The material of the lead frame is connected with gold or silver composition and connected using spot welding.
The terminals cannot match the performance with tin or other materials, the industry packages them with gold or silver finish to match industry standards. The frequency of operation is majorly impacted by the choice of lead.
The solder pad part is protected by plastic packages which provide relative permeability for performance, especially for surface mount packages.
Lamination techniques over ceramic substrates and adaptable in organic substrates not only withstand high temperatures (thermally reliable) but are also less expensive. The electrical durability is more than other ceramic substrates.
