Ball Grid Array 0201 and Surface Mount Technology
Ball grid arrays (BGA’s) represent one form of surface-mount technology (SMT) which is being used more and more today in the production of integrated circuits because of their many advantages. A decided improvement over the conventional quad flat pack style packages, the BGA package has much less potential for problems arising from close solder bridges and poor joints, because spacing is less congested. With pin congestion becoming problematic on those older style packages, a newer technology was needed to make the transition to higher efficiency and higher reliability. Some of the improvements offered by BGA package technology:
- Easier reworking – larger pad sizes make rework easier when it’s necessary
- Manufacturing yield – because soldering on the PC board is much improved, and there is more space between connections, yield is higher
- Better use of space – the entire printed circuit board space can be used, rather than just the peripheral areas
- Thinner package – this is very useful because it meshes well with industry needs to create thinner assemblies for modern devices such as cellphones
- Thermal and electrical performance improvements – BGA packages can direct heat away via the pads, and can use power and ground planes for lower inductance, along with controlled impedance traces for signals
Why ball grid array technology?
BGA technology has an entirely different way of applying the connections on a circuit board, and that approach is largely responsible for the advantages outlined above. Past strategies for implementing PC board connections called for using the sides of the package for connections, and that forced pins to be spaced very closely together – and to be manufactured much smaller – so as to maximize use of available space. Contrary to that approach, BGA makes use of the package underside, where there is much more usable space.
Instead of having pins for connectivity, BGA uses solder balls which are placed on the underside of the chip in a grid pattern. The BGA device is then fitted on to the printed circuit board, where there are matching copper pads that actually provide the connectivity. Because the conductors are positioned on the underside of the chip carrier, the leads on the chip are shorter, which reduces lead inductance. All this adds up to a higher performance level than most other surface-mount technologies are able to muster.
BGA 0201 technology is at the very cutting edge of surface-mount electronics, and represents a significant improvement over its predecessor, the 0402 package. Shrinking passive components in to the package size of the 0201 has been made possible by advances in current, working voltage, and power dissipation needs of modern high-frequency circuits. Greater use of compact components and precision circuit design have increased high-frequency capabilities because component ESL can be minimized, as well as the reduced path route on the PC board. Because the 0201 components are extremely compact, they must be placed with a very high degree of accuracy, which means manufacturing methods must be very precise, and subject to strict quality control measures.
At present, 0201 technology has only seen limited use in manufacturing applications, primarily where miniaturization is called for. Mobile phones and other mobile equipment, as well as high-frequency modules are prime users of the 0201 package, although increased usage is undoubtedly around the corner. With the undeniable advantages afforded by ball grid array technology and the miniaturization benefits of the 0201 package, it is certain that BGA 0201 will come to have wide usage as a surface-mount technology in the coming years.