MBE Components, Standard Electron Beam Evaporator EBV

EBV

Standard Electron Beam Evaporator

EBV 200-100-SR
  • UHV compatible, low outgassing

  • High flux rates of low vapour pressure materials

  • High-purity evaporation

  • Hearth volumes: 40 cm³ or 100 cm³

  • Long filament lifetime

  • Easy maintenance

  • Optimized versions for SiGe MBE available

EBV 200-100-SR e-beam evaporator on DN200 (O.D.10") CF-flange, equipped with manual linear shutter, integrated refill unit & Si shielding parts

Download IconData Sheet


The Standard Electron Beam Evaporator EBV - is an evaporation source intended to achieve high growth rates for low vapour pressure materials, especially when high purity of the evaporant is desired. Large hearth capacities ensure a long system up-time before evaporant is depleted.
Our series of standard electron beam evaporators EBV are single-pocket UHV evaporators mounted horizontally on base flanges from DN150 CF up to DN250 CF. For all models a mounting-slide is offered that allows easy handling and service of the EBV.

Only UHV-grade materials are used for its construction without any compromise, obtaining a design that is bakeable up to 250°C. In the hot areas of the emitter only high-purity low vapour pressure materials like Mo, Ta, W or Al2O3 are present.

The electron emitter is designed with 270° beam deflection, eliminating nearly all ion bombardment effects on the filament. The electromagnetic coils are manufactured from KaptonTM (polyimide) isolated wires and nickel-plated magnetic steel, the permanent magnets are of a high temperature rare earth material and the single-hearth crucible is manufactured from a high purity OFHC-copper block (Oxygen-Free-High-Conductivity Copper). The crucible capacity can be chosen between 40 cm³ and 100 cm³, machined into the copper block. The cooling of the copper block is effectively accomplished by two complete turns of water bores closely around the hearth.The electron emitter is designed in a way that eliminates nearly all ion bombardment effects on the filament. This is due to the 270° beam deflection and the very sharply bent electron beam path near the exit of the asymmetrical emitter aperture. Thus it is well shielded from evaporant or charged particles ejected from the crucible (see Fig. in the right. In addition, the 270° emitter design shields the sample from a direct sight onto the hot tungsten filament further reducing the chance of sample contamination by impurities from the hot emitter area.


Single pocket Cu-hearth

Single pocket Cu-hearth, capacity 100 cm³



Principle of e-beam evaporator operation

Principle of e-beam evaporator operation


Application

EBV evaporators are designed for high rate evaporation of low-vapour-pressure materials, especially when high purity of the evaporant is desired. They are frequently used for evaporation of refractory metals, e.g. Mo, Nb, Ta, W, Zr, it is well suited for high-rate evaporation of Al, and of course also for semiconductors like Si and Ge. A typical application of the EBV is SiGe MBE.

For application in a silicon MBE system we provide a specially adapted set of shielding parts manufactured from high-purity single-crystalline silicon. These plates and rings cover all parts of the metallic body that are potentially subject to electron or ion bombardment and that face the substrate. Only this Si-shielding allows the growth of highest purity Si-based films with virtually no metallic contamination. We also supply high purity Si source material in superior quality, machined from wafer-grade Si-single crystals, fitting the evaporator hearth closely.

For germanium evaporation with the EBV 200-100, a crucible liner made from high purity silicon is available. Ge does not sublime but has to be molten completely for evaporation. To prevent it from interacting with the copper hearth, this "Si-crucible" is used, leaving a capacity of about 50 cm³ for the Ge evaporant.

For metal deposition the EBV can be used "as is" for all metals that do not melt completely or that do not react with the cooled Cu-wall. For some metals, graphite- or other metal crucible-liners are used. Ask for the solution for your particular evaporant.

Technical Data

Mounting Flange
DN150 CF (O.D. 8"), DN200 CF (O.D. 10") or DN250 CF (O.D. 12")
Filament type short-legged coil of thick W wire, electron emitting filament
Operating pressure 1 × 10-11 mbar ….1 × 10-5 mbar
Acceleration voltage 4 - 10 kV
Beam power max. 10 kW, (3 kW; 5kW; depending on power supply)
Filament current max. 50 A at 10 V (AC)
Spot size 5 mm diameter, approx
Primary beam deflection 270° by permanent magnet system
Dymamic beam deflection coils wound from KAPTONTM - isolated wire;
x-deflection current: ± 3 A; y-deflection current: ± 3 A;
deflection frequency: max. 150 Hz
Bakeout temperature 200°C (all air side connectors removed)
Cooling water cooling, connectors SwagelokTM 8mm (air side);
water flow min 8 l/min at 3 bar
Crucibles 40 cm³ or 100 cm³ hearth volume
Options water cooling hood with custom apertures integrated on base flange (K);
integrated custom-made source shutter (S) with optional drive unit LSM 40-100;
integrated refill unit ERU 16 (R)



Crucibles

The most commonly used crucible material is PBN; other materials are available as required. Please refer to the Selection Guide or inquire for detailed recommendations. For information on crucibles see Crucibles.

Dimensions

Schematic drawing EBV Schematic drawing of the Standard Electron Beam Evaporator EBV

(Drawing shows EBV 200-100-S)



Specific data

For general information on CF mounting flanges see Flange and Gasket dimensions.

images/header_refill_unit.gif
[cm³] [mm] / [mm] [kW] / [mA] Product code
EBV 150 - 40 - LxxxD150 10 / 1000 HV
EBV 150 - 100 - LxxxD150 10 / 1000 HV
EBV 200 - 40 - K S * R** - LxxxD195 10 / 1000 HV
EBV 200 - 100 - K S* R**- LxxxD195 10 / 1000 HV
EBV 250 - 40 - K S * R**- LxxxD245 10 / 1000 HV
EBV 250 - 100 - K S* R**- LxxxD245 10 / 1000 HV
* manual or automated shutter actuation (with LSM 40-100)
** Si recharge block Ø36x20, mass 45g
*** specify UHV length L with order


Product code:

e.g. EBV 200-40-KS-L250D195

is a standard electron beam evaporator on DN200 CF flange with 40cm³ hearth capacity, water cooling hood and integrated linear shutter, in-vacuum length 250mm and diameter 195mm.