Aluminum-base PCB production focus shifts to multilayer types

	This Aluminum-5 model from Finest features a black solder mask and has 1.5mm board and 1oz copper thickness.

China’s aluminum-base PCB suppliers are shifting focus to multilayer variants on the back of growing demand from applications requiring elevated density, reliability and stability, small size and light weight. The type currently accounts for a minority share of the output, which is driven by single- and double-sided kinds. Makers, however, are optimistic multilayer versions’ share will increase in the months ahead. Output now yields models with four, six, eight, 10 and 12 levels.

Hamp Science & Technology Co. Ltd will ramp up production of multilayer varieties this year to take advantage of robust orders from high-power LED providers. Shenzhen Jaleny Electronics Co. Ltd, meanwhile, aims to explore the category in coming years.

Makers are also enhancing thermal conductivity and resistance and heat dissipation.

R&D efforts will likewise emphasize more compact dimensions. To this end, manufacturers are reducing the minimum line width/spacing, hole diameter, and dielectric and base layer thickness. The last two typically range from 76 to 152μm and 0.5 to 3mm, respectively.

Aluminum-base variants account for 10 percent of China’s overall PCB yield. The share may climb to 15 to 20 percent as companies boost turnout by more than 30 percent amid a rebounding world economy. After overall revenue hit $1.8 million in 2010, Hamp will double production this year to achieve $3.5 million in sales.

LED lighting, power supply, computer, household and communication applications are the main growth drivers for the line. Demand from the first will continue to gain more steam, owed to the prevailing trend for environment-friendly illumination and the popularity of LED products. Because of their high heat dissipation, low thermal resistance and long operating life, aluminum-base PCBs are widely used in LED indoor and outdoor lighting. The annual revenue from the segment is projected to surge by more than 40 percent in the next few years. The application base will be broadened further as North America and Europe suppliersbegin to phase out fluorescent bulbs.

Statistics from the China Electronics News indicate the LED lighting industry will experience a 33 percent CAGR by 2012, with total market scale reaching $1.3 billion worldwide. Meanwhile, sales of LED backlights used in LED TVs are forecast to climb by more than 30 percent in the next two years, which augurs well for aluminum-base PCBs. The Ministry of Science and Technology has recognized the cities of Shenzhen and Dalian in Guangdong and Liaoning provinces, Chongqing municipality, and Jiangsu and Zhejiang provinces as key production hubs for such components for LED applications.

Aluminum-base PCBs are likewise employed in SMT. Compared with ceramic kinds,the former has greater heat dissipation, longer service life, and better durability and reliability. The variant also offers lower operating temperature and installation cost.

To bolster the segment further, China suppliers will expand application to other fields such as audio devices, automotives, solid-state relays and rectifier bridges. Demand from these areas is projected to exceed 30 percent.

Under efforts to ensure safety and quality, companies are conforming to UL in addition to ISO 9001 and 14001. About 1,200 PCB makers in the country are working to acquire the first.

ODM and OEM transactions account for the bulk of manufacturers’ business, so R&D efforts will also emphasize customization. Hamp will improve designs as client-specified orders remain the priority. The enterprise will likewise shorten delivery period from the current 5 to 10 days to 1 or 2 days to attract more orders.

There are about 200 aluminum-base PCB makers in mainland China at present. Only a few offered this variant in the past due to higher production requirements compared with traditional PCBs. Strong margins, however, have been encouraging suppliers to enter the line.

Overseas players from Taiwan and Hong Kong are expected to transfer manufacturing bases to the mainland to take advantage of low costs.

PCB selections
Hong Kong: Lighting sector buoys aluminum-base PCB line
Product gallery

Companies offer mainly single- and double-sided types with 3.94 to 11.81mil line/width spacing and 0.15 to 1mm hole diameter. Products have a surface finish of HASL, lead-free HAL, ENIG, immersion gold or OSP, with the first two being the mainstream. Shenzhen Jaleny’s selections use lead-free HASL.

Aluminum-base PCBs can be classified as universal, and high thermal dissipation and frequency based on performance. The first employs epoxy-glass fabric bonding sheet for the dielectric layer. Models with greater thermal dissipation feature epoxy resin with elevated heat conductivity. Polyolefin or polyimide resin glass fabric adhesive tablets make up the high-frequency board category.

Aluminum types consist of the circuit, dielectric and base layers. The first contains a printed circuit that connects parts placed on PCBs. The dielectric layer has a ceramic-filled polymer that boasts low thermal resistance, high anti-hot aging, thermal conductivity and insulation. Aside from aluminum, copper is an option for the base.

The processes involved in making multilayer kinds are board cutting, drilling, plating and etching. A series of QC inspections is also conducted. Production equipment is purchased from foreign partners to ensure high quality.

Materials account for more than 80 percent of the total outlay. The key components are aluminum base and copper foil, which are sourced from local providers or overseas partners on request. For the dielectric layer, mainland makers use thermal conductive electrical insulation requirement usually obtained from foreign vendors such as Bergquist of the US. Taiwan companies also offer inputs with high thermal conductivity and insulation performance.

As copper and aluminum costs increased by more than 20 percent in the past year, many enterprises raised quotes by 10 percent. Finest Printed Circuit Board Ltd adjusted rates by 15 to 20 percent in 1Q11 to offset elevated material and labor spending, which registered a 20 and 30 percent jump, respectively, last year.

Shenzhen Jaleny has retained prices for key clients, but it plans to charge 5 to 10 percent more for new customers to make up for the steep overhead.

Suppliers anticipate material expenses to continue climbing for the rest of the year, although adjustments may be limited to 10 percent. As for 2012, aluminum-base PCB prices are forecast to remain stable.

Shenzhen Jaleny turns out 1,000sqm of these variants a month. Double-sided models typically have 1mm board thickness and 0.3mm hole diameter. The minimum line width/spacing is 4mil.

Makers of aluminum-base PCBs in Hong Kong are developing models suitable for LED lighting products such as lamps, streetlights, displays and even commercial luminaires. Releases likewise target applications with surface-mounted high-power components, including networking boards and amplifiers.

Selections from the territory constitute mostly single- and double-sided variants. Multilevel kinds, which may exceed four layers, can accommodate aluminum cores or heat sinks. Those with 1 to 1.66mm aluminum base are mainstream.

Other enterprises concentrate on flexible and rigid-flex PCBs. ANS Industrial Co. Ltd offers the last and high-precision double-sided rigid types.

To meet varying customers’ preferences, manufacturers provide a range of surface finishes such as OSP, white solder mask, HAL, tin plating and immersion gold. Options at ANS include HASL, lead-free HASL, selective, immersion and palladium gold, silver and tin, carbon print, gold finger, flux coating, peelable mask and LPI.

Hong Kong makers likewise emphasize technical specifications, particularly heat-dissipation features. Circuitone Ltd is banking on years of experience in the power supplies industry to fix problems related to this attribute.

Manufacturers carry out heavy copper, hard gold-plating, laser drilling, blind/buried vias, selective plating and thin cores services. Some also conduct in-house assembly and chip mounting.

The supplier pool caters to clients from Europe, North America, Japan and Southeast Asia. For the past 20 years, key player Onpress Printed Circuits Ltd has been providing aluminum-base, multilayer and rigid-flex PCBs and flexible circuits to Fortune 500 companies and multinational enterprises.

Related reports:
PCB assemblies: Suppliers emphasize design, R&D capability boost
HDI PCBs: Portable electronics, new applications spur industry growth
Multilayer PCBs: Makers boost capability to ride out challenges

Circuitone Ltd
(Hong Kong)

Model: Aluminum-base PCB
Description: One layer; immersion gold surface finish; aluminum-based copper-clad laminate substrate; white silkscreen; 1.5mm board thickness

Epotek Electronics Co. Ltd
(Taiwan)

Model: Metal Core PCB
Description: One layer; aluminum; OSP surface finish; 110mm diameter; 1.6mm board, 1oz copper thickness; for building lights

Goldenlight Electronics Co. Ltd
(Taiwan)

Model: MCPCB
Description: Metal core type; 0.9 to 3mm. board thickness; 0.78W/mK dielectric thermal conductivity; 170 C glass transition temperature; 600x600mm board dimensions; for LED panels; RoHS

Hamp Science & Technology Co. Ltd
(mainland China)

Model: MK-AL-01
MOQ: Negotiable
Delivery: 7 days
Description: Four layers; 500x600mm; 1.6mm board, 75±5ìm dielectric, 36±3ìm copper thickness

Onpress Printed Circuits Ltd
(Hong Kong)

Model: Aluminum-base PCB
Description: 16 layers; 1/3 to 4oz copper base; HASL, lead-free HASL, ENIG, flash, thick or selective gold, OSP, OSP/HASL, immersion tin or silver surface finish; buried via; 22x26in; 4oz copper thickness

Parason Industries Ltd
(Hong Kong)

Model: Parason-07
Description: Two to 16 layers; FR-4, CEM-3, Teflon, aluminum substrate, Rogers, halogen-free, high-Tg base; lead-free HAL, HAL, flash gold, OSP, gold finger plating, carbon ink printing, peelable blue mask, immersion gold, tin or silver surface finish; green solder mask; blind, buried, micro vias

Shenzhen Jaleny Electronics Co. Ltd
(mainland China)

Model: JLYAL-503
MOQ: Negotiable
Delivery: 10 days
Description: Single-sided; lead-free HASL surface finish; 19.69mil minimum line width/spacing; 1.6mm board thickness; for LED lights; UL