High Vacuum Exposure Test Facilities

The department runs several high vacuum and ultrahigh vacuum instruments with base pressure 10-5 to 10-11 mbar e.g. two thin film deposition facilities with electron beam and resistive heating or instruments for surface analysis like Auger. Presently, one of these chambers is reconstructed to house a device for measurement of Coefficient of Moisture Expansion (CME). Chambers may also be adapted to test performance of mechanisms under space environment. A stock of spare parts and instrumentation, both for high vacuum and ultra high vacuum technique, including vacuum chambers and turbomolecular pumps is available, which can be used in a flexible way for ad hoc measurements.

Thermal vacuum chamber (TVC)

The aim of the test facility is the simulation of thermal vacuum conditions, typically for the simulation of space environment (open space and sun exposure) on parts up to 600 x 800 mm2.

The simulation of the satellite surface temperature will be done by means of a temperature controlled copper plate mounted inside the vacuum chamber. The main part of the device is a 0.8 m in diameter and 1.2 m long (volume: 0.6 m3) vacuum chamber made out of stainless steel (s. Fig.). The vacuum pressure of better than 10-5 mbar will be achieved using a VARIAN DS 602 rotary vane pump together with a VARIAN TV 1001 turbo pump (1000 l/s). The control of the vacuum pressure will be done by a VARIAN ConvecTorr (gauge tube for rough vacuum) and a VARIAN IMG-100 (Inverted magnetron high vacuum gauge).

The chamber is equipped with 4 CF40, 2 CF63, 2 CF100 and 1 CF200 flanges on the front door, 4 CF40, 4 CF63, and 1 CF200 flange on the back side and 1 CF 200, 2 CF 150, 2 CF 63 and 4 CF 40 on the circumference of the chamber. These flanges will be used for the feed-throughs for the cooling and heating devices and the connection of the necessary measurement devices for the characterisation of the test object (thermocouples, Si-diode sensors, heat flux sensors, etc.).

The equipment used is an Eurotherm 2408 with Thyristor and an Eurotherm 2416 with Thyristor for temperature control. 20 PT100 (OMEGA Thinfilm RTD Element F3105) for measurement of the temperature at several positions inside the TVC and a Keithley 2000-20 Multimeter incl. IEEE – card for importing the data to the PC. By means of a heating / cooling plate and a heating / cooling pot the test item can be heated up to about 300 °C and cooled down to liquid nitrogen temperature max.

Medium Ultra High Vacuum Facility

This facility consists of a medium UHV-chamber (1m diameter x 1.5 m length,<10-7 mbar) used for testing of set-ups for space experiments. It is equipped with electronic supplies, dataloggers and enables the exposure to electron and/or ion beams as well as to microdust loading.

Emitter Test Facilities

Three facilities are run for the development of ion emitters. Climate tests, e.g. after DIN 50 014 "Standard atmospheres", DIN 50 017 "Condensed water containing climates, or EN ISO 6988 "Metallic and other non organic coatings - Sulfur dioxide test with general condensation of moisture". mbar) used for testing of set-ups for space experiments. It is equipped with electronic supplies, dataloggers and enables the exposure to electron and/or ion beams as well as to microdust loading.