Several types of simple non-evaporable getter (NEG) assemblies have been constructed using a commercial St 707 strip or a St 172 module. Each assembly is mounted on a conflat flange with an outer diameter of 203, 70, or 34 mm (CF203, CF70, and CF34, respectively) and can be activated by direct current heating. The pumping speeds of the three NEG assemblies (the CF70-mount type using a St 707 strip, the CF70-mount type using a St 172 module, and the CF152-mount type using a St 707 strip) have been measured for N₂ and H₂ gasses at 20℃. The maximum pumping speeds for the three types of NEG assemblies were 4.8, 1.2, and 25 L s⁻¹ (8.0, 3.6, and 82 L s⁻¹) for N₂ (H₂), respectively. These NEG assemblies are useful for laboratory ultrahigh vacuum systems as well as vacuum ultraviolet/soft-X-ray beamlines in synchrotron radiation facilities.

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  Hydrogenated amorphous silicon (a-Si:H) nanoball film emits photoluminescence only after being thermally oxidized, because the oxidized film is sufficiently transparent that excitation laser light can reach Si nanocrystal. We fabricated amorphous silicon nitride (a-SiNH) nanoball film by reacting N₂ plasma and SiH4 gas. Without being thermally oxidized, this film was highly transparent and exhibited photoluminescence. The source of this photoluminescence is presumed to be either the quantum size effect of Si nanocrystal or electronic transitions in siloxane (Si-O-Si), which is present at the interface between Si nanocrystal and SiO₂. By coating the a-SiNH nanoball film with SiN film, we fabricated a-SiNH nanoball film that was siloxane-free but that exhibited photoluminescence. Hence, we attribute the observed photoluminescence to the quantum size effect of Si nanocrystal.

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