Automated welding is a staple of the modern production environment. Yet different processes – i.e., implementations – demand vastly different tools. Automobile manufacturers, for instance, often employ laser or plasma welders attached to robotic arms – file footage many of us are familiar with from recent economic news. Other applications require greater sophistication so that the weld itself does not interfere with the functionality of the finished product.

For many of these applications, manufacturers’ materials and products require that welds not only be very precise or very small; many the weld itself – essentially a bond of melted material – must be free of contaminants or warping so that the finished good can function as intended. In the semiconductor manufacturing environment especially, the welding environment must be purged with inert gas to “shield” the arc from atmospheric gases that can make their way into the arc itself or contaminate the weld itself.

Executing this weld requires special weld heads that are capable of fitting tightly to the material to be welded – e.g., a tube, component, or substrate – to create a seal. The space around the weld is then purged with an inert gas or gas mixture. Gas argon is most commonly employed. The weld head produces a small channel of conductive gas inside the “shield gas” through which electric current is conveyed by a tungsten electrode, thereby creating an arc of consistent size and temperature. The channel of conductive gas and the tungsten electrode can be programmed to move according to precise instructions to execute a weld that is free contaminants and is consistent in quality – both properties being essential to the proper functioning of semiconductor components.

Yet weld heads are not only available for GTAW or TIG welding. As mentioned, there is a design suited to nearly any process (or otherwise the potential for an inventor to become very rich filling the gap), and energy for a weld can be conveyed through laser, plasma, etc.

When purchasing a weld head for a process, buyers who only consult with an OEM do themselves a disservice. Vendors of equipment from multiple OEMs have the expertise to choose the right tool for the process, and those who also have experience in repair and re-manufacturing may be able to offer a remanufactured weld head at a fraction of the price of a new one purchased from an OEM, without any sacrifice in quality.

Since its introduction in aerospace manufacturing during the 1960’s, orbital welding has allowed for the advancement of efficiency in even the most complex and demanding manufacturing processes. In no manufacturing process is this as evident than in the process for manufacturing semiconductors and solid state components, wherein welds must be smaller and more precise than any human could conceivably implement. Whereas for other, larger metal technologies – like planes and boilers – orbital welders offer not only precision but economic efficiency, orbital welding in the semiconductor process is not only efficient but necessary. To accommodate advances in semiconductor technology, orbital welders must follow suit, becoming more and more precise with each new generation of arch machines and weld heads.

Advancements in welding technology have been  facilitated in large part by the advancements in gas delivery, which allow a weld head to produce a microscopic arc to fit very small components or tubes together or to the substrate. First, local inert gas purification provides a high-purity welding environment that keeps the arc consistent and prevents the material being welded from becoming contaminated by contact with hydrogen, oxygen, or other atmospheric gasses. Second, advancements in mass flow controllers have made it possible for gasses to be dispensed in molecular amounts, allowing for a microscopic conductive environment through which arc current can travel in the inert environment to implement the weld.

A weld head for semiconductor applications differs from other industrial counterparts mostly in its precision. This precision takes a number of forms. First, the the tungsten electrode that creates the arc will usually be smaller and sharper than it is for other applications, since this focuses current and produces smaller welds that would be far too small to support the weight of heavy metals, etc. Second, the head will usually be designed to provide a high degree of protection against gas leakage (fit tightly) because the gasses used to generate an electric arc for semiconductor manufacturing are usually volatile and often lethal to human clean room workers. Third, a semiconductor welding head will be manufactured for maximum durability, since the stresses of welding could cause defects to the head that would compromise not only safety but weld quality, rendering a welding component unsaleable.

Selecting the right welding components for a specific production process is as much a science as the science behind welding itself. Each manufacturer’s head will have its own setup that will need to be integrated into the entire process – a configuration that should only be left to experts. Employing a vendor who also offers expert configuration ensures that the system is not only the safest but also the most efficient for any given production process.