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PEZ 63-60-54-DF, production effusion cell on DN63 (O.D.4.5") CF-flange
with conical 60 cm³ crucible, dual filament version with two separate power feedthroughs on DN16 CF flanges |
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- Precise run-to-run flux reproducibility
- Crucible capacities 40-420 cm³
- Customized beam shaping crucible inserts available
- Most effective heating system
- Excellent reliability and long lifetime
- Standard, cold lip and dual filaments
- Optional: integrated cooling shroud
- Compatible to fit Varian, EPI, Veeco, VG or Riber systems
 Large Capacity Ga/In Production Effusion Cell Data Sheet ( 196 kB pdf-file )
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The Production Effusion Cell PEZ was designed to meet the particular requirements of production MBE systems with higher throughput.
The temperature range 200-1400°C allows evaporation or sublimation of a large number of elements and compounds, including standard III-V and II-VI MBE materials such as Al, Ga, In, As, Zn, Se.
Standard, cold lip and dual filament types are available, covering different evaporation material requirements. The picture on the right details a dual filament mounted in a PEZ.
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Dual filament heating system of PEZ 63-60-54-DF |
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PEZ cells are equipped with conical or cylindrical crucibles, offering precice flux reproducibility and excellent thickness uniformity.
Further improvements of source material utilization and flux stability are achievable by the use of a customized beam shaping PBN insert in combination with a large capacity crucible.
Such an insert is shown on the right, mounted into a PEZ 63-130-54-DF, especially designed for Ga and In deposition.
The crucible insert not only reduces the effect of filling level related flux changes, but does also act as an thermal buffer which virtually eliminates shutter transients (see clause "Application" below).
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PEZ 63-130-54-DF large capacity Ga/In production
effusion cell with customized crucible insert |
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Similar to our standard effusion cells, the crucible is heated by a tantalum wire filament supported by PBN rings. The advantages of this heating assembly are described on page "WEZ".
The consequent use of power and TC feedthroughs on separate DN16 CF flanges (see picture nearby) allows easy servicing. Completely closed power connectors with gold-plated contacts guarantee easy and safe handling of the PEZ.
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Airside view onto a PEZ 63, connectors for
dual filament cell (left) and for SF/CL options (right) |
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The standard crucible material for the PEZ is PBN. We offer a wide crucible capacity range from 40 to 420 cm³.
The picture on the right shows a PEZ 100-420-84-CL with cold lip-filament version suitable for 420 cm³ crucibles with lip diameter 84mm. This large cell is used as evaporation stage in our "VGCS" GaP Compound Source, for example.
For large scale production systems even larger crucible capacities are available on request. Please inquire our headquarters for further information.
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PEZ 100-420-84-CL with cold lip filament design |
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Application
The PEZ is recommended for elements and compounds evaporated or sublimated at temperatures in the range 200-1400°C, e.g. Al, Ga, In, As, Zn, Se, etc.
Compared with our standard effusion cell WEZ, the PEZ is distinguished by a more robust cell design and the consequent optimization of many details to provide even higher stability and reproducibility, excellent reliability and easy servicing. Thus our PEZ is ideally suited to production MBE systems.
For MBE applications requiring a wide-area homogeneous growth, we recommend the use of conical crucibles (e.g. cell type PEZ 63-40-51-K). Our specially designed compact hot lip filament improves the critical power management in the upper crucible zone and reduces the heater wire temperature, thus reducing the chemical corrosion. In addition the more robust radiation shielding and cell heater housing, as well as flange protection tubes, reduce the risk of chemical corrosion and electrical short-circuits caused by liquid metals (gallium).
Especially designed for Ga or In deposition in III-V MBE systems, the PEZ with large cylindrical crucibles (130 cm3 or larger) can be equipped with a customized crucible insert. The use of a very large crucible with a beam shaping insert combines the advantages of conical and cylindrical crucibles:
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Beam shapes of bottlenecked SUMOTM crucible, PEZ crucible with insert and conical crucible |
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- The crucible insert provides conical beam shaping, which results in minimized waste of material and excellent uniformity.
- Conical crucibles show the effect of filling level related flux changes, because of the continuous change in evaporation material surface. This effect is highly reduced for PEZ with insert, because the surface is constant during a growth campaign.
- Shutter transients are a common problem for layer growth when using standard crucibles with wide orifice. The influence on the thermal stability of the molten material caused by shutter action is virtually eliminated by the crucible insert’s function as a thermal buffer and by the use of dual filament heating.
- Dual filament heating allows keeping the conical insert at higher temperatures to avoid material condensation.
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The Large Capacity Ga/In PEZ offers high material efficiency, up to 25% better than SUMOTM type cells.
The PEZ 63-130-54, for example, with 130 cm3 crucible and insert has a maximum Ga load of 500 g, depending on cell positioning on customer's MBE system.
With 420 cm3 crucible the maximum Ga load is increased to 2000 g.
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