New from ALMA: UCA Cleanroom Services

Cleaning to UCV standard, ultra-clean assembly (UCA), and the reliable packaging of clean products

ALMA cleaning services after component production

Ultra-clean components thanks to pre-cleaning to the required standard

Clean components are increasingly becoming a basic prerequisite for the production of high-precision quality products. However, before fine cleaning in the cleanroom can take place, the components have to be processed to ready them for the cleanroom. This includes the removal of solid and liquid production residues (particles, oils etc.).


Ultrasonic cleaning bath at ALMA’s Plant I
In its Plant I, ALMA operates a cleaning line in which freshly machined components undergo spray-cleaning, ultrasonic cleaning and osmosis water rinsing before being double-packaged in film bags under cleanroom conditions (ISO 8) and conveyed for further assembly (UCA) to Plant II.

Cleaning to cleanroom standard

  • Removal of organic residues
  • Removal of production-related particles


Cleanroom cleaning to UCV standard

Preparing components for processing in an ultra-clean vacuum


On admission to ALMA’s new UCV cleaning unit, a badge is affixed to each component for identification and documentation.
During the planning of the new ALMA cleanrooms, special importance was attached to equipment free of organic substances and the design of standardised process stations. The outcome is optimum cleanroom processes subdivided into admission (ISO 7), cleaning (ISO 6) and assembly, testing and packaging (ISO 5).

On admission a badge is affixed to each component for identification and documentation.

Where demanded, we subject components to UHV high-temperature bake-out in which material surfaces with a particularly high standard of cleanliness can be achieved by desorption (see further down).

Cleaning processes in the ALMA cleanroom

  • Ultrasonic cleaning with the aid of multisonic baths
  • Ultrasound-assisted interim rinsing and final dipping, both with deionised water
  • Manual pre-drying with ultra-pure processed nitrogen; residue-free final drying


Multisonic bath used in the new ALMA cleanroom cleaning process (ISO 6)

Thermal cleanroom processes

Vacuum drying oven in the ISO 5 cleanroom

Right at the transfer station from the cleaning area (ISO 6) to the ultra-clean area (ISO 5), a special vacuum oven with an oil-free vacuum pump has been installed.


Vacuum oven for thermal treatments
In this vacuum oven, thermal treatments for specific components are performed. After component pre-drying with nitrogen, the range of treatments in the vacuum oven extend from simple vacuum drying to high-temperature processes (bake-out) in which material surfaces with a particularly high standard of cleanliness can be achieved.

Thermal cleanroom processes

  • Assistance of final drying
  • Enhancing the cleaning result by baking out components

Cleanliness inspections

Measurement and documentation of surface cleanliness


Visual inspection is possible with white or UV light.
So that components meet the highest standards of cleanliness, they undergo strict control in the test laboratory before being packaged.

Modern, calibrated test equipment is available in the new ALMA cleanrooms (ISO 5) for the measurement and assessment of particle contamination.

ALMA cleanroom test equipment

  • Cleanospector measuring
  • Visual inspection under white and UV light
  • Checking with an optical microscope
  • Fluorescence measuring device
  • Tensiometer
  • Particle counter
  • Wipe tests
  • Water break tests

Checking particle contamination with an Cleanospector

ALMA assembly services in the cleanroom

Ultra-clean assembly (UCA) services


With continuous training, ALMA trains its cleanroom staff to the latest UCA cleanliness standards.
With its new ISO 6 cleanrooms, ALMA is in a position to offer customers cleanroom assembly services extending from the assembly of UCV components through to complete, tested units.

Components with a weight of up to 1,000 kg undergo ultra-clean assembly to the highest standards of cleanliness.
The intelligent layout of the new test laboratory facilitates not only component control, but also, for example, the leak-testing of complete units. For this, the helium leak test equipment is docked onto the cleanroom from the grey room so that contamination from the test set-up can be reliably excluded.

Cleanroom packaging services

Packaging and labelling to customer specification


Packaging is also performed in the ISO 5 classified cleanroom.
To uphold the achieved standard of cleanliness during transport and protect the components and assembled units from fresh contamination, they are packaged under cleanroom conditions (ISO 5).

For products destined for further cleanroom processing on the customer’s site, this is done with double packaging in an ultra-pure inert gas atmosphere so that they can be re-admitted to the cleanroom without contamination.
The packaged products are marked to customer specification with UCA-certified labels applied to the inner film package.

ALMA cleanroom packaging services

  • Welding in certified PE bags or with composite films
  • Use of ultra-pure N2 inert gas atmosphere
  • Labelling to customer requirements with cleanroom-compatible materials
  • Outer packaging with PE film