Metal in the Board – What It’s All About
The combination of power and intelligence made possible by the digitalization of power supply, conversion, and control (Fig. 1) is becoming an enabling factor for an expanding range of new and existing opportunities.
Semiconductor technology is also driving another entirely new application: Solid State Lighting. Illumination technologies have been dominated by single, bright sources- from primitive bonfires through candles, oil, and gas lamps to the incandescent bulb. LEDs are only the 4th technology introduction in the history of lighting, but they are driving fundamental changes in the way lighting is designed and used. In comparison to incandescents, where a ‘white hot filament’ is the source of light, the LED doesn’t need to be hot to work. Indeed the junction temperature needs to be kept below about 110°C while the device dissipates some 75% of input power in the form of heat. The heat produced is much less than for the incandescent but none the less the few watts involved have to be extracted from a very small volume of the LED or loss of intensity and premature failure are guaranteed.
In their just-released report “Metal In the Board- Opportunities for Printed Circuit Boards Providing Enhanced Thermal and Power Management “- BPA Consulting provide a unique window on the business of Metal in the Board (MiB). This term groups metal core, metal base, and an expanding array of innovative thermal and power management technologies.
The report identifies and profiles a number of board level solutions for the management of heat and power, the applications for which these are suitable, and the market opportunities represented by the applications themselves. These solutions employ both conventional and enhanced printed circuit fabrication techniques and materials to create metallic structures in the circuit board, supporting power densities up through 20W/cm2 and currents as high as 1000 Amperes in combination with the level of interconnect that is currently available from PCBs- ranging from simple, single layer circuits up to complex HDI multilayers using low loss dielectrics.
What’s Driving the MiB Market
BPA are expecting board shipments incorporating MiB to grow from some $2.4 billion in 2013 to nearly $3.4 billion in 2020. Within a global growth rate of about 5% per year some technologies will be losing market share and others will be growing in excess of 50% p.a. BPA sees this growth as being driven by four key factors:
- New generations of power semiconductors provide a low impedance thermal path via a pad on the underside of the package, and have been shown to shrink board area by as much as 60% and reduce assembly costs as bolt-on metal heatsinks are replaced by surface mount on MiB. This means a substantial increase in power density with surface mounted assembly for applications ranging from electrical power control to RF power amplification for mobile communications.
- Solid State Power conversion and control is replacing mechanical and hydraulic controls in an expanding range of Automotive applications, enabling improved fuel economy, lower weight and an increase in speed of response.
- LEDs need to run relatively cool, with semiconductor junction temperatures held at or below 110°C to attain maximum luminous efficiencies and life expectancies of up to 50,000 hours. Low cost, passive cooling must ensure a low resistance thermal pathway from the junction, through the chip and packaging, then through the interconnect structure and out to ambient.
- The build out of UMTS and ramp up of LTE mobile communications requires thermal management at the power amplification stage of the base transceiver stations at the heart of each network cell, with RF Power amplifiers dissipating hundreds of watts in the form of heat. The evolution of package types from ceramic to plastic leadless with bottom side thermal pads is driving an increase in power densities of at least 3X as form factors decrease.
How Big is This Opportunity and How Fast is it Growing?
The MiB opportunity is complex and evolving rapidly, particularly in the automotive and lighting sectors.
- Automotive currently dominates the MiB landscape, with value installed in automotive subsystems representing some $775 million in 2012. Based on industry unit forecasts, Tier 1 roadmaps, subsystem technology profiles and NPI development timing, BPA forecast this figure to grow to about $1.4 billion in constant 2012 USD by 2020.
- Other highlights include Solid State Lighting, which is expected to require nearly $500 million in finished board value by 2020 with Digital Power and Power Generation/Management reaching $280 million and nearly $500 million in the same period. These figures represent double digit average annual growth rates.
In addition to the applications themselves, the report looks at current and forecast growth trajectories by MiB type, offering an invaluable aid for capacity/capability roadmapping and planning.
- MLBTV Types (boards incorporating thermal vias) dominated MiB production in 2013, as these types bring together established printed circuit materials and process technologies to provide a high conductivity thermal path through the board.
- BPA are expecting the IMS2 type (metal substrate insulated with enhanced thermal conductivity dielectric) to grow at more than 30% CAAGR, reaching nearly $800 million in the next few years, but to then begin a decline through and beyond the end of the decade as SSL replacement volume requirements drop and new installations become the dominant market driver in commercial and residential lighting.
- BPA’s forecast models indicate that the fastest growth will be seen in new technologies. Many of these are either proprietary or involve highly specialised know-how unique to their developers, all of whom are printed circuit manufacturers: highlighting the opportunity that this new applications arena represents.
Don’t Get Left Behind
BPA’s just-updated Metal in the Board Report brings additional coverage of dynamic new markets as well as the most recent data to the extensive review of technologies and markets presented in the first edition. Advances in automotive subsystems, selective MiB technologies, and new applications opportunities add to the solid background in thermal and current management technologies and markets which make this report essential reading for industry participants ranging from applications engineers and designers to strategists concerned with business technology and development.