Animation of the 2 evaporation modes: rod and crucible evaporation:
Step 1: filament gets glowing and electrons are emitted Step 2: high voltage is applied to the evaporation rod Step 3: rod gets hot and starts evaporating Step 4: due to electron collision some evaporated particles get ionised (illustrated blue) Step 5: evaporated material exits through front aperture Step 6: the negative biased flux electrode collects ions as means for the flux last sequence shows the change from rod to crucible mode
Mini E-Beam Evaporator is an UHV evaporator for small and medium
of almost any material in the temperature range of 400K to 3100K.
is possible either directly from evaporant in rod form
or out of a crucible. An integrated flux monitor allows maximum
control. Highly efficient watercooling ensures negligible outgassing
operation. The e--flux electron beam evaporator
is very compact
and mounted on a CF-40 flange (2.75"OD). It can easily be retrofitted
existing UHV or MBE systems as the mounting orientation is virtually
Main applications of the e--flux
Mini E-Beam Evaporator
are in surface science, thin film deposition and doping.
Most common evaporation materials are such as Mo, Ta, W, Au, Ag, Pt,
Al, Cu, Ni, Ti, C, Si, Cr and others.
features of the e--flux
Electron Beam Evaporator:
almost every material possible
Dual mode operation
from rod or out of crucible (e-beam heated effusion cell)
Simple rugged construction
using only standard feedthroughs
various control options, wide range of crucibles and many other options
In the evaporation zone of the e-beam evaporator a
filament (ground potential) is placed in the close vicinity of an
conducting crucible or target (high positive potential) and provides
which are accelerated towards the evaporant rod/crucible producing
high heating-power densities. The evaporation hearth is highly
watercooled to ensure negligible outgassing.
is rugged for long term trouble free operation. Only standard
are used even for the
and even for the watercooling lines to minimise
and enabling the user to self-service at any time.
The filament can easily be replaced and can be self-made using standard
The power supply of the e-beam evaporator
is a conventional, rugged design which delivers up to 600W to allow
medium quantities of material to be deposited (>1nm/s). However,
of the emission current makes evaporation of very low rates
easy and reproducibly possible.
electron beam evaporator can be tailored to almost any application
using a wide range of options
such as flux monitor, shutter, thermocouple, extended rod feed, many
materials and others.
Unique new features of the e-flux mini e-beam
alert rod feed2
setting of desired emission current3
current stabilizer is a closed
loop control to
keep the emission
automatically with rod melting down or decrease of crucible content
alerts when the evaporation rod
has to be fed. Threshold can be customer set.
emission current can now be set directly
on a linear scale for easy reproduction.
option allows to deflect all charged particles out of the beam.
beam evaporator can be used to evaporate material in 3 ways:
mode: The material in rod form is directly bombarded by electrons and
rapidly to evaporation temperature. Rod evaporation is generally
because it creates purest films (only evaporant is heated), no crucible
employed (no crucible cost, no alloying) and evaporation from all
possible. However, some materials such as those with high thermal
and low melting points need crucible evaporation (below). Rod
is suitable for refractory metals and other materials which reach high
partial pressures e.g. 10-1 Torr before melting.
is evaporated, more can be fed into the evaporation zone, using the
effusion cell mode:
The material is placed in a conducting, usually refractory metal
which is heated by electron bombardment causing the contents to
Optional temperature control of the evaporant via a thermocouple and
controller make this mode identical to more conventional effusion
Effusion cell mode is intended for insulators or other poor electrical
conductors and low vapour pressure materials such as gold and aluminium
which melt before reaching useful vapour pressures.
wire technique': The material in form of a thin wire is winded around a
rod, typically Tungsten. In a first step the material is melted onto
the Tungsten rod and afterwards evaporated by electron bombardment.
This method is especially suitable for materials which cannot be
evaporated from rod directly and are alloying with conventional
crucible materials. Typical evaporants for this technique are Platinum
Mini Electron Beam Evaporator (with
all options) and controller
Application of the e--flux
Mini Electron Beam Evaporator:
applications of the e--flux electron beam
evaporator are in thin film
growth for surface science, MBE, doping, metalization, atomic layer
deposition, optical films, oxide films and others. Materials used are
e.g. Mo, Ta, W, Fe, Cr, Ti,
C from rod and Au, Ag, Al, Cu, Ni out of a crucible. Some
materials like Pt have been successfully evaporated by using a 'wetted
evaporation is dome as standard
from Ø2mm rods. Due to the powerful power supply evaporation
from 3, 4, 5 and even Ø6mm is possible. As
the rod evaporates it has to be from time to time fed with a linear
motion drive. This can be done without breaking the vacuum, not even
discontinuing the evaporation.
rates can be achieved from sub-monolayers per minute up to several nm
per second. Typical values are for refractory materials as W, Ta, Mo
max 3-5nm/min and Ag, Cu, Al max 1nm/sec.
The e-flux ebeam evaporator can be controlled:
manually with PI control of emission
controlled (flux controller
option and crucible mode required)
Features of the e--flux
Mini Electron Beam Evaporator:
evaporator / e-beam heated effusion cell provides a number of new
and advantages over previous designs:
is constructed using simple and rugged technology which permits high
beam powers up to 600W standard to be generated without the use of
a small coil consisting of several turns of tungsten wire as opposed to
‘hairpin’ and short-wire filaments. Because the
filament fully surrounds
the target, more uniform e-beam heating with consequently improved flux
distribution can be achieved. Replacement filaments are readily
from tungsten wire and easily exchanged thereby minimising operating
(optional) can be used to monitor and stabilise the target temperature.
The thermocouple can be used, as in any other K-Cell as part of a
control loop comprising a PID controller and the optional control input
on the power supply.
are used to minimise servicing costs and downtime in case of
failures. The watercooling lines are flange mounted (CF16,
and can hence be disassembled easily. The rod feed driven by a
linear motion feedthrough found in most vacuum components catalogues.
is available. This is an additional electrode which intercepts
edge of the emerging vapour beam. As the vapour leaves the crucible/rod
it is partially ionised by the incoming electron beam. Some of the ions
will be collected by the flux monitor electrode, generating a small
current which is related in magnitude to the vapour flux.
flux monitor a flux controller (PID) is available to keep the flux
emission surface provided by the tungsten coil filament
e-beam powers to be used at lower filament temperatures than in
filament designs, with consequently extended filament lifetime. The
is simple in form. Replacements may of course be purchased or be easily
fabricated by the user from tungsten wire.
power of max. 600W allows rods with larger diameters (up to 6mm) to
evaporated or crucibles with larger volumes can be used (up to 400mm3).
turn means that higher evaporation rates can be obtained because of the
larger evaporation area and that more material may be evaporated before
refilling is required. Besides the increased evaporation rates this
also allows higher quality films. As the homogeneity of thin films is
improved with larger distance, the disadvantage of lower deposition
rates can therefore easily be compensated.
design of the
evaporator allows rods of up to 50mm in length to be fed into the
of e-flux Mini E-Beam Evaporator (with oüptions)
of the e-flux mini e-beam evaporator:
options). Special length possible on request.
pyrol. Graphite, BN liner, Al2O3, Quartz
(±12° with flux monitor)
19" rack mount,
or 115VAC/60Hz or 100VAC/50Hz
Controller: for many years the flux measurement of the e--flux
Mini E-Beam Evaporator has been established to indicate the deposition
growth rate. Besides flux monitoring a PID control was available to
the flux/rate constant.
As a new
option for the electron beam evaporator we now a
Deposition Controller is offered. This extends the flux based
by features as known from quartz microbalances. The Deposition
can automatically run a process only by input of the desired film
and the evaporation rate.
is an ideal tool for users who often want to evaporate different
or evaporation rates from known material. Parameters of up to 9
and processes can be stored after an initial calibration. A user
software is provided. Via an RS232C interface the process can be
needs the flux electrode option and it’s recommendable to
have a motorised
shutter for automatic end point control.
up to 9 materials/process
interface for control
interests of continuous
product development, specifications of the e--flux
Mini Electron Beam Evaporator are subject to change without