EFFICIENCY AND EVALUATION - Total-Reflection X-Ray Fluorescence Analysis and Related Methods - page 410

6.3PERCEPTIONANDPROPAGATIONOFTXRFMETHODS
A brief overview of previous TXRF instrumentation and its worldwide appli-
cation has already been given in Section 1.2.1. A more detailed description
of today's commercial instruments and their worldwide distribution shall
demonstrate the perception and propagation of TXRF and related methods.
Furthermore, efforts concerning standardization, international activities, and
cooperation shall be enumerated.
6.3.1CommerciallyAvailableInstruments
In the last decade, the TXRF market changed considerably. Two major compa-
nies no longer exist (Technos and Atomica), another manufacturer no longer
supplies TXRF instruments (Cameca/FEI as successor of Atomica), and Seifert
has stopped the production of TXRF instruments. The company G.N.R. (initials
of the owners) supplies the instruments formerly distributed by ItalStructures.
On the other side, the ATI (Atominstitut in Vienna) constructs a spectrometer
designed for academic use only (like the previous Wobi module) and a small
company, OurStex in Japan, manufactures a new portable instrument.
At first, an overview of today's commercially available instruments will be
given before dealing with particular instrumental developments. Table 6.5
summarizes five current manufacturers or suppliers of complete TXRF spec-
trometers (ATI, Bruker, G.N.R., OurStex, and Rigaku). The different suppli-
ers with sites, instruments, excitation, monochromators, detectors, weight, and
particularities are listed here. Half of the instruments have high-power X-ray
tubes so they need water-cooling; the other half have low-power tubes, which
are air-cooled. Most instruments use a multilayer for monochromatizing, only
one uses an X-ray waveguide, and all these new instruments offer an SDD
detector instead of a Si(Li) detector.
Many instruments are benchtop devices like the Wobistrax from ATI, the
Picofox from Bruker, and the Nanohunter from Rigaku. Half of all spectrom-
eters have a sample changer and allow vacuum measurements. The Wobistrax
is produced by the nonprofit ATI and is distributed to scientific institutes only
as mentioned earlier. The only portable spectrometer is the 200TX of Our-
Stex [100,101]. It is equipped with a low-wattage X-ray tube of 5 W [102] and
the sample chamber can be flushed with nitrogen gas [103]. The company G.N.
R. supplies the TX2000, which allows a choice between TXRF with
(0 ° /90 ° ) geometry and conventional XRF with (45 ° /45 ° ) geometry. The Nano-
hunter of Rigaku is suitable for GI-XRF measurements with an angle scan up
to 2 ° . Several further ingenious devices of Rigaku are available for TXRF
analysis in the wafer industry. They need a room of a whole lab possibly with an
ultraclean environment and are applicable for wafers up to 300 mm and even
450 mm in diameter. Rigaku is headquartered in Tokyo, Japan, but other
affiliated companies are located in Japan, in the USA, and in Europe (in Kent,
UK, and Berlin, Germany).