Thermal Cracker Cell TCC

The Thermal Cracker Cell TCC is an effusion cell with additional cracker stage inside an integrated water cooling shroud on a space-saving DN40CF flange.
  • Full PBN solution for corrosive materials like Te, Sb, Se, As, Mg
  • DN40CF ( O.D. 2.75" ) mounting flange c ompatible with all MBE systems
  • Thermal cracking up to 1300°C
  • 35 cm3 or 130 cm3 PBN crucible
  • Excellent thermal isolation between low temperature reservoir and hot cracking zone
  • Integrated water cooling for cracker stage
  • Integrated rotary shutter  Datasheet

Introduction

The Thermal Cracker Cell TCC is an effusion cell equipped with a cracker stage with integrated water cooling shroud on its space-saving DN40CF ( O.D. 2.75") flange. The cell features a crucible size of 35 cm 3 or 130 cm3 which is sufficient for most R&D applications.

TCC zones
TCC zones
TCC zones
TCC time-temperature diagramm for heating of the cracker only The aim of the TCC is to reduce the thermal crosstalk of the cracker and the reservoir.

The TCC is designed for evaporation of materials at operation temperatures from 100°C  to 650°C with an additional cracker stage on the end of the injector tube that provides temperatures up to 1300°C.

The crucible is heated by a tantalum wire heater. The standard crucible material suitable for most evaporants is PBN.

The shielding of the crucible is reduced to optimize the cell for low temperature operation. That way a good flux control for high vapor pressure materials is possible without using an additional valve.

The crucible and cracker zones are shrouded by water cooling therefore the thermal load on the chamber is neglectable.

This is realized by excellent thermal insulation between the low temperature reservoir and the hot cracking zone.

The figure on the left shows the temperature response of tube and crucible in case of heating the cracker only.

The temperature is measured by thermocouples on application critical positions: within the cracker zone, the tube and at the bottom of the crucible.

Even at cracker temperatures around maximum temperature of 1300°C the temperatures of tube and crucible stay unaffected to a large extend.

Application

A source concept like this is used for high vapor pressure materials, which form atom clusters. Typical evaporation elements are As, Se, Sb, Te, Mg.

Technical Data

General
Mounting flangeDN40CF (O.D. 2.75")
In-vacuum length L220 mm or 287 mm
In-vacuum maximum total length TL240 mm or 307 mm
Maximum airside length OL405 mm
In-vacuum diameter D36 mm
Maximum airside radius AR106 mm
Shutter distance DS15 mm
Shutter opening angle90° ccw
Bakeout temperature200°C
Cooling water flow30-90 l/h
Weight13 kg
Maximum chamber pressure10-5 mbar

Reservoir
Heater typeTa wire filament
ThermocoupleNiCr/NiAl (type K)
Operating temperature100°C – 650°C
Outgassing temperatureUp to 700°C
CoolingIntegrated water cooling shroud
Crucible capacity35 cm3 or 130 cm3
Crucible materialPBN

Tube
Heater typeTa wire filament
ThermocoupleW5%Re/W26%/Re (type C)
Operating temperature200°C – 800°C
Outgassing temperatureUp to 850°C
CoolingNone
Tube materialPBN

Cracker
Heater typeTa wire filament
ThermocoupleW5%Re/W26%/Re (type C)
Operating temperature300°C – 1200°C
Outgassing temperatureUp to 1300°C
CoolingIntegrated water cooling shroud
Cracking insert materialPBN

Crucibles

The most commonly used crucible material suitable for most evaporants 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 TCC
Schematic drawing of the Thermal Cracker Cell TCC (drawing shows TCC 40-130-54-KS)

Specific data

For general information on CF mounting flanges see Flange and Gasketdimensions .

ProductCF flangeNominal capacityLip diameterCoolingShutter*UHV dimensions***
[mm]
max. electrical
[W]/[A]
Power supply
product code
Crucible
product code
[cm³][mm][mm]/[mm][W] / [A]Product codeProduct code
TCC40 -35 -37 -KS-LxxxD36reservoir 300/8
tube 100/5
cracker 150/8
PS 36-12
PS 36-12**
PS 36-12
CRU 35-37
TCC40 -130 -54 -KS-LxxxD36reservoir 400/8
tube 100/5
cracker 150/8
PS 60-10
PS 36-12**
PS 36-12
CRU 130-54

* rotary shutter possible on same flange ** optional *** specify UHV length L with order (L=220 mm or L=287 mm)

Product code:
e.g. TCC 40-130-54-KS-P-L220C36

is a Thermal Cracker Cell on DN40 CF-flange for an 130 cm³ crucible (lip Ø 54 mm), with integrated water cooling shroud, shutter, PBN crucible, in-vacuum length 220 mm and outer diameter 36 mm.