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СВЕРХНИЗКОТЕМПЕРАТУРНЫЕ ЯЧЕЙКИ |
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VERY LOW
TEMPERATURE CELLS
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- Operating range between 50 & 400°C
- Stability better than +/- 0.01°C
- Rapid flux stabilization
- Single and Double Zone heating models available
- perfect solution for high vapor pressure materials
(polymers/organics, Hg, Cd, Te, Se, Zn..)
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VERY LOW TEMPERATURE /HIGH TEMPERATURE STABILITY EFFUSION CELL FOR POLYMERS / ORGANICS / OTHERS
Organic MBE is a very promising technique in the research for novel semiconductor materials and the design of new opto-electronic components. The technique involves, however, the use of new kinds of source materials which exhibit very high vapor pressures at low temperature.
Conventional effusion cells are not adapted to work properly at such low temperatures (50 to 100°C) and give both poor temperature stability and poor temperature change dynamics. This is due to their excessive thermal mass and inadequate thermal exchange with the source environment. Conventional T/C’s (even K type) are also not well adapted for use at such low temperatures.
ADDON design:
The ADDON design is a completely new, and patented, concept of effusion cell which has improved temperature stability/reproducibility and good thermal agility at low temperature. A Platinum Resistance Temperature sensor (PRTD) is used for the temperature measurement and control. Each source is equipped with its own cold source which gives a very efficient thermal response.
As observed for some more common source materials, certain polymers are best evaporated in a Double Thermal Zone scheme source. In this case, two independent thermal units (cold source/hot source/temperature sensor) are used so as to adapt the temperature gradient to the source material behavior. |
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Figure 1
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Figure 2
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Performance:
Figures 1 & 2 illustrate the time response and the long term temperature stability of a Double Zone Very Low Temperature source used at 60°C. Top and Bottom temperatures are stabilized within +/- 0.01°C.
Stable temperatures can be obtained in less than one minute, starting from ambient.
General Information:
- System installation: The cell uses a CF flange and can be installed on any of the major commercial MBE system ports. The low temperature range of this source permits use without LN2 or water cooling. Since the source uses very low power air flow cooling is adequate.
- Power Supply: The recommended operation requires a DC or AC power supply of 5 Amp x 80 volts and a good quality PID controller with a PRTD (PT100) sensor entry. (Eurotherm 900 or 2000 series for example)
- Source capacity: Two models with PBN 25 cc or 60 cc crucibles are available. The crucibles are, as for a standard cell, very easily exchangeable.
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MBE
Manufacturer |
MBE
Model Number |
Min
Connecting Flange |
Crucible Capacity (cc) |
Source
Model Number |
Crucible
Model Number |
| RIBER |
1000/32/2300 |
DN40CF 2,75" |
25 |
VLT25RB3 |
835025 |
| VG |
V80/90 |
DN63CF 4,5" |
60 |
VLT60VG8 |
7630360 |
| Varian |
Varian 360 |
DN40CF 2,75" |
25 |
VLT25VA2 |
835025 |
| Gen II |
DN63CF 4,5" |
60 |
VLT60VA3 |
763060 |
| Others* |
upon request |
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60 or 25 |
VLT60 or 25 |
763060/835025 |
| * Please ask ADDON if you have special requirements (eg. cell length, flange size, capacity etc.) |
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