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The K1250X Independent Cryogenic Freezing, Preparation & Transfer System

A 'self contained' (independent) preparation system, with a turbo molecular, high vacuum pumping unit to allow the freezing, K1250X Cryo SEM System | Image Pop Up preparation, transferring, and subsequent examination of frozen hydrated specimens in a Scanning Electron Microscope and Field Emission SEM, without the need to utilise the SEM vacuum system.

The System will interface to all the current range of SEMs and the component parts will allow reverting to ambient temperature applications to be readily achieved.


System Items:

Preparation Unit

Freezing Chamber
Preparation Chamber
Turbo Pumping Unit

Control Unit

Sputter Coating Module
Carbon Coating Module
Vacuum sequence module
Turbo Control Unit
Temperature Monitoring Unit
Film Thickness Monitor

Transfer Unit

Transfer Device with Integral Gate Valve
Specimen Stub

SEM Components

Liquid Nitrogen
(Standard) cold stage with conducting braid cooling
(Alternative) cold stage with gas flow cooling
Access Gate Valve



Features:

  • Remote control user interface
  • Remote electronics & systems operations
  • Independent preparation chamber
  • Cooled knife probe facility
  • Turbomolecular pumping facility
  • Low voltage 'cool' sputtering head with high repeatability
  • Carbon fibre 'flash' evaporation head
  • Transfer unit (actively evacuated) with gate valve
  • Radiant heater head for surface sublimation

Benefits:

  • Low interference due to remote electronics
  • Low vibration due to independent sample preparation
  • High resolution sputter coating (optional)
  • Freeze fracturing due to cooled knife & probe facility
  • Adaptable to any SEM
  • Carbon & gold can be run together
  • Microscope can be easily reverted to ambient operation
  • Ultra-clean system due to turbomolecular pumping
  • Specimens can be sublimed remotely from the microscope

System Performance:

Freezing Chamber
Integral high vacuum chamber to produce sub-cooled liquid nitrogen for specimen plunge freezing. Pump down time 30 secs. Sub-cooled (slushy) nitrogen at -210oC. Fitted with locating collar to suit transfer device, and excess pressure relief valve.

Preparation Chamber
Integral high vacuum chamber, axial mounted, with single action, self locking, access gate valve, and dead space pumping to suit transfer device, to facilitate all preparation facilities 'in-situ', and subsequently, with turbo pumping unit.

Turbo pumping unit 'axial' mounted on preparation chamber, with full 'throat' ISO63 flange to ensure maximum pumping efficiency. Pumping speed 60L/Sec. Vacuum better than 1 x 10-5mbar. Safe shut down to atmosphere in event of vacuum failure, without damage.

Preparation chamber cold stage with four (x4) working positions, and copper to copper conduction, maintaining stage temperature colder than -170oC, fitted with full cold shield contamination protection.

Preparation chamber liquid nitrogen dewar. Double walled vacuum pumped, with one (x1) Litre internal capacity at atmosphere pressure maintaining stage temperature under quiescent conditions for 60 minutes without 'top up' or 'autofeed'. (Approx. 10 Litres per day.)

Sublimation stage integral to preparation chamber cold stage, with controlled temperature and timer.

Micrometer Adjustable Knife with cooled 'blade' and adjustable height and push / pull action, with sample clearance feature on return stroke.

Macro manipulator with cooled 'point', and adjustable pivot positioning.

Sputter head (Standard), low energy input, high resolution. With Gold target (0.1mm thick x 20mm Dia.) fitted as standard. At 20mA, 100V dc (mean) for 2 minutes, thickness 20nm. Grain size 2nm.

Specimen temperature increase less than 3oC/minute. Vacuum control for sputtering needle valve range 5X10-1 to 2 x 10-1mbar with electromagnetic 'back up' valve.

Sputter head Chromium coating head.

Carbon head for flash evaporation technique using carbon cord/string, with high vacuum turbo pumping giving fine coatings and allowing several evaporations from carbon cord without changing source.

Control Unit
Control unit with plug in modular electronics and low voltage (24V dc) control circuitry.
Liquid Crystal Display with small compact keypad. Controller "black box" can be situated away from keypad.

Sputter Coating Module with variable deposition 0-50nm/minute (Gold), and current control 0-50mA on analogue meter, with sputter voltage range 80-120 volts mean dc., and 0-4 minutes reset deposition timer.

Carbon coating module with low voltage 20V ac supply for carbon evaporation 'flash' typically one second, with 0-50A ammeter and variable outgas current control 0-20A.

Radiant heater with low voltage 20V ac supply with variable current control 0-20A.

Vacuum sequence module with electromagnetic valves, and automatic turbo backing pressure interlocking. Continuous vacuum monitoring of preparation chamber analogue meter 0 to 1x10-5mbar. Auto select vacuum monitor of all other points of the system analogue meter 0 to 1x10-5mbar.

Turbo control unit interlocked to vacuum sequential with normal (high vacuum) indication, and failure mode sensing.

Temperature monitoring units for preparation chamber cold stage and SEM cold stage. Set point control in range +50oC to -200oC, with P.I.D. (Proportional, Integral and Derivative) control parameters, and digital display +50oC to -200oC controlling input stage heaters, with adjustable timing 0-20 minutes. (Full range of controls -200oC to +400oC) Accuracy better than +/- 1oC.

Transfer Unit
Transfer chamber actively vacuum pumped for contamination-free applications. (Vacuum better than 1x10-2mBar during Transfer.)

Transfer rod with thermal insulated tip, and integral single action, self locking gate valve, with dead space pumping facility.

Specimen stub, polished copper, with good thermal transfer characteristics and 'holding' properties. Warm up less than 10oC/minute during transfer activities when not located on cold stage. Facilities for longitudinal, crossectional, and fracture rivet applications.

SEM Components
Liquid nitrogen dewar, with interface to SEM port, to facilitate cold stage cooling and anti-contamination shield. Double walled vacuum pumped, with one (x1) Litre internal capacity at atmosphere pressure maintaining stage temperature under quiescent conditions for 60 minutes without 'top up' or 'autofeed'. (Approx. 5 Litres per day.)

(Standard) Cold stage with conductive braid cooling. Designed to fit existing SEM stage, with thermal insulators, and maintaining all reasonable stage movements with copper braid conductive cooling to liquid nitrogen dewar. With sublimation and timer control. (Approx. cool down from ambient (20) to -160 typically 30 minutes.)

(Alternative) Cold stage with gas flow cooling. Designed to fit existing SEM stage, with thermal insulators, and maintaining all reasonable stage movements with copper braid conductive cooling to liquid nitrogen dewar with sublimation heater and timer control. (Approx. cool down from ambient (20) to -160. Typically 20 minutes.

SEM single action, self locking, access gate valve with interface to SEM port, and dead space pumping to suit transfer device.

System General

Valves
Three (x3) manually operated access gate valves are single action, self locking, to prevent inadvertent operation.

Needle valve for sputtering control fitted with non damaging seat, with pre-set position control, and electromagnetic back up.

All other operational valves are electromagnetic, with push button control, with full mimic status indication.

Input valve for argon gas supply.

Input valve for nitrogen gas supply. (Recommended, but can be operated from one common gas supply: Argon)

(Option) Pressurised 30 Litre supply dewar for provision of N2 Gas and liquid nitrogen. With auto top-up for the system dewars from either conductive braid cooling OR gas flow cooling AND nitrogen gas supply for gas flow cooling.

Specifications of the K1250X Cryo SEM System:

Instrument Cases - 450mm W x 350mm D x 175mm H
International Standard DIN 41494, with integral air flow, and E.M.C. Standards (Electro Magnetic Compatibility).
Fitted with
Cylindrical Work Chamber - 130mm Dia x 250mm Long, with Vacuum Gate Valve
Slushing Chamber - 125mm Dia x 150mm Deep,
Liquid Nitrogen Dewar - 100mm Dia x 150mm Deep, Capacity 1.0 Litre
Turbo Molecular Pump - 60L/Sec.
Weight - 36Kg.

Control Unit - 450mm W x 350mm D x 175mm H.
Fitted With
Control Electronics
Weight - 28Kg.

Transfer Unit with
Vacuum Gate Valve - Vacuum Pumped
SEM Coldstage - With Vacuum Gate Valve and Liquid Nitrogen Dewar 1 Litre Capacity.
Weight: - 16Kg
Total Weight of System - 82Kg

Sputter Coating - 20mm Dia x 0.1mm Thick Target (Gold fitted as standard)
Timer - 0-4 Minutes.
Sputter Gauge - 0-50mA.
Carbon Coating - Deposition 0-10nm/min Carbon Fibre/Carbon Cord (with Integral Radiant Heater)
Ammeter Gauge - 0-50 Amps
Evaporate Button
Outgas Control - 0-25 Amps
Cooled Knife Assembly
Cooled Probe Assembly
Specimen Transfer Stub
For Multipurpose applications (special stubs available)
Vacuum Gauge - 0-1x10-5mBar
High Vacuum Condition Indicator
Turbo Molecular Pump Unit - Better than 1x10-5mBar
Preparation Stage Temperature - Better than -170oC
Temp. Monitor & Control - -200oC to +50 (Control full range - 200oC to + 400).
Timer - 0-20 Minutes
SEM Stage Temperature - Better than -170oC
Temp. Monitor & Control - -200oC to +50 (Control full range -200oC to +400)
Timer - 0-20 Minutes
Viewing Light Source

Accessories
Accessory pack, with consumable items, sufficient for an initial
operating period. (Inclusive)
Gas supply small bore plastic tubing and fittings.
Power supply cord and plug, for country of operation.

Options
 Pressurised 30 Litre liquid nitrogen supply dewar for auto top- up and purging requirements.(When using gas flow cooling - provides nitrogen gas supply)
System bench mounted or supplied with custom trolley
Binocular Microscope on Preparation Unit

Operating Instruction
To include full interfacing and installation procedures, all Manual operating parameters and specimen preparation techniques, and application references (Inclusive)
Installation & Training - Installation and training on site, for two working days. (Additional)

Services Required
Regulated argon gas supply, 5 p.s.i. for sputter coating
Regulated nitrogen gas supply, 5 p.s.i. for purging
Liquid nitrogen supply 15L/day normal usage (Recommended 25L storage dewar)

Vacuum Pump - Double stage rotary vacuum pump 10m3/Hr with oil mist filter and vacuum hose. (Recommended No.10 - Optional
Requirement)

Electrical Supply - Single Phase 230 volts 50Hz. 8 amp max. including Pump.
OR
Single Phase 115 volts 60Hz 16 amp max. including Pump