Special Gases

In the manufacture of nanometer-sized structures, the ingress of particles 10-100 times larger than the functional elements themselves can lead to the complete destruction of the device. Since these devices are manufactured for a long time, from several days to several weeks or more, the discovery of an inoperative device at the final stage of its production leads to enormous losses of both time and human resources, and materials.

When designing the FMN Laboratory facilities, the experience of large microelectronic enterprises was taken into account. The team analyzed the world's leading centers and their infrastructure subsystems, and made a comparative analysis of suppliers of equipment for special gases, suppliers of gases themselves, as well as a thorough analysis of companies involved in implementing these solutions. As a result, a highly reliable conglomerate was formed from leading American and German manufacturers, which jointly implemented a system for providing special gases at the highest level.

FMN Laboratory uses 15 special highly pure gases with a purity up to class 6.0 (99.9999%). That is why, at FMN Laboratory, special attention is paid to the safety of employees, the environment and equipment. So, especially dangerous toxic and explosive gases and gas mixtures are located in a separate room on the street, where an uninterrupted power supply system, a separate exhaust, and supply ventilation system, gas neutralization system (scrubbers), as well as a compressed air supply systems for pneumatic valves are implemented.

All highly hazardous gases are located in specialized armored fireproof gas cabinets of a leading American manufacturer. These cabinets are fully automatic, which means that using gas or changing a gas cylinder requires nothing more than the standard procedure for disconnecting and replacing a new cylinder. All necessary actions for supplying gas to the line, as well as for monitoring the cylinder pressure (in the case of gaseous reagents) or its weight (in the case of liquid reagents) are carried out by the automation. Accordingly, a signal about the need to change the cylinder is also issued automatically when the cylinder is empty to a certain level.

FMN Laboratory has implemented a four-level system for monitoring and warning of emergencies. This includes, first, monitoring the smallest gas leaks. The lines of all highly hazardous gases are made in the form of coaxial pipes, the outer shell of which is filled with an inert gas. In the event of any depressurization or damage to the pipeline, the inert gas pressure drops, the system triggers an alarm and instantly stops the gas supply. In addition, in gas cabinets, as well as in each technological installation that uses gas, highly sensitive gas analyzers of a leading German manufacturer are installed, which include an alarm in case of detection of hazardous gases several times lower than the permissible level, which is still safe for humans.

At the second security level, continuous control of the exhaust ventilation flow (100-200 m3 / h) is carried out. In the case of a slight decrease, a warning is issued, and in the case of a sharp drop – an alarm and a complete shutdown of gas supply. This exhaust ventilation is intended solely to remove accumulations of gases, which can occur only because of an accident or damage to the pipeline. In a properly functioning system, gas accumulation does not occur; however, exhaust ventilation operates 24/7.

The third level of security is an automatic fire extinguishing system, and the fourth level is a highly reliable emergency warning system. Therefore, for example, in case of the slightest threat of a gas leak in a room on the street, all cleanroom personnel inside the building will be notified and evacuated.

In order to conduct scientific research and obtain results that correspond to and exceed the world level, FMN Laboratory pays special attention to the purity of materials from which and with which high-tech devices are made. In addition to imposing stringent requirements on the purity and quality of substrates, metals for deposition and other starting materials, the quality and purity of chemicals, water and, in particular, special gases are also carefully controlled.

As indicated above, FMN Laboratory uses 15 special highly pure gases with a purity up to class 6.0 (99.9999%). In the process of certification from the acceptance tests of gas pipelines, they were purged for several days, which made it possible to achieve a moisture and oxygen content of up to 100 ppb (parts per billion). All gas pipelines are equipped with additional purifiers located in close proximity to technological equipment and increasing the purity class of individual gases to 8 (99.999999%), and the pipelines themselves are made of high-quality German steel with a roughness Ra of less than 250 nm.

In addition to certification and acceptance tests of gas supply systems, the Center introduced the experience of the world's leading microelectronic enterprises, thanks to which a special technique for working with special gases has been developed. In addition to the use of gas distribution panels of a leading German manufacturer, the procedure for changing used cylinders has been put into practice, which includes many stages of purging the section of the pipeline with inert gas, as well as complete evacuation of the line during the day. This allows us to obtain identical and repeatable results over a long period, whether it is a plasma-chemical etching of silicon and its oxide or the deposition of thin films of noble metals.