Storing Gas for Semiconductor Manufacturing

A reality of manufacturing chips or wafers of any kind is that some kind of inventory of dangerous gas must be kept on-hand and that the economics of employing all of it at once in an automatic gas cabinet are not that compelling. Consequently, gas that is either extremely flammable or otherwise corrosive and lethal needs to be stored in a manner that will not threaten the environment – both in production and around it – and the people in and around the production area.

One of the main ways this is done in real world manufacturing is by keeping gasses housed separately from the production area in an environment that can be sealed and decontaminated remotely – an environment that really doesn’t different much at all from a clean-room except that in it isn’t used for production, since dust, humidity, and other impurities can compromise valves, regulators, and pose hazards to both safety and quality of production. Sensors are employed to detect any leaks before they become hazardous so they can be addressed. And fire safety equipment is abundant so that even a spark can be extinguished, lest it become something more. Rooms that are too warm pose a threat to some more volatile compressed gasses, since temperatures significantly higher than room temperature can raise pressure in the tank to the point of explosion.

Gas cylinder cabinets add another level safety to storage versus leaving cylinders stacked or standing upright in the ground. Gravity being what it is, round cylinders can often be unruly, and the slightest disturbance can knock them over, causing them (in very rare cases) to leak, spark – or, in the rarest and most dangerous of cases – both leak and spark simultaneously. Cabinets provide a good resting place for cylinders that will keep them steady. A well-fitted one will even keep things relatively stable during an earthquake.

Of course, gas cylinder cabinets can be automated with manifolds and an on-board computer and transformed into an automatic gas cabinet that can dispense gas to the process site from a remote storage location. This is not prohibitively expensive and some argue that it is safer than storing large inventories of gas outright since there are more valves between the gas itself and the atmosphere.

Still, the reality of semiconductor manufacturing is that dangerous gasses must be used and that sometimes inventory beyond what is needed for a production cycle must be kept on hand. In such cases, a solid galvanized cabinet placed in a good storage location will provide an added level of safety.