Festo pneumatic drives reduce contamination from semiconductor processing equipment

Festo pneumatic drives reduce contamination from semiconductor processing equipment

Festo pneumatic drives reduce contamination from semiconductor processing equipment

Keywords Festo, Cleanrooms, Contamination, Semiconductors

Festo pneumatic drives have been selected as a cleaner and more compact alternative to conventional electric drives by German semiconductor automation equipment specialist Jenoptik Infab.

In searching for a solution to the demand for improved semiconductor lab cleanroom standards, German equipment specialist Jenoptik Infab, discovered that the biggest source of particles comes from the semiconductor process equipment itself. Moving machine parts such as guides, drives, cables and hoses generate particulate matter due to mechanical contact, and this dust contaminates the cleanroom's atmosphere.

Triggered by this discovery, Jenoptik embarked on an R&D programme aimed at finding a way to minimise the contamination generated by process equipment. After much research, the company found that a major part of the solution lay in replacing the existing motor and spindle-based electric drives in its latest series of lab automation equipment with a cleaner pneumatic alternative from Festo.

The Festo pneumatic drives are hermetically sealed and consequently produce minimal particulate matter, what little there is coming from the cylinder sealing rings. This contamination can be removed by vacuum before it can cause a problem.

The industry standard wafer diameter will soon be 12", and 0.2µm silicon features are being superseded by 0.18µm technology. And during its production, a wafer can undergo around 200 process steps. The wafer dimensions, diminutive feature size, and complex process combine to heighten the risk that the smallest particles can render individual chips on the wafer useless.

Some reject chips are inevitable, but as their complexity and size continues to rise, so does their cost. In order to safeguard profit margins, semiconductor manufacturers will need to find new and innovative ways to reduce the number of chip rejects, and one route to this is by improving cleanroom standards.

Conventional approaches to maintaining minimal contamination in the cleanroom involve pumping purified air vertically through an entire production area, and dressing employees in protective clothing. Although this is a highly practical and popular method, it reaches its limits at about one particle per cubic metre of air. This may have been acceptable in the past, but manufacturers now need to adopt a higher standard. The Jenoptik equipment incorporating Festo pneumatic drives claim to provide the answer.

Jenoptik now incorporates the highly compact Festo pneumatic drives into its latest Ergospeed and Fixload series of automation equipment. In addition to their cleanliness, the Festo drives satisfy Jenoptik's demand for the full range of complex automation movement sequences needed for its products. Jenoptik now also uses Festo pneumatic drives for a range of other process equipment used for wafer alignment, actuation of gates and locks, and coupling and gripping.

Festo pneumatic drives are equipped with integrated vacuum extract ports. Exhaust air is ducted and returned without causing contamination. This means that cleanroom users immediately enjoy the advantages that Festo drives offer by simply connecting directly to their existing class 1 compressed air system.

In addition to cleanliness, Festo pneumatic drives offer a whole host of other advantages over conventional electric motor drives. These include: operating at up to four times the speed of motor drives; being up to 40 per cent smaller in size; lighter in weight; quieter in operation; easier to handle and almost entirely maintenance-free.

As the demand for higher cleanroom standards increases, the correct selection of semiconductor process equipment will be vital for minimising particulate contamination and maintaining a clean environment.

Further details: Nicola Meadway. Tel: 01252 775000; Fax: 01252 775001; E-mail: nicola.eadway@festo.com