Oxford Instruments OptistatDry BL4 User guide

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
System Manual
Oxford Instruments
Issue 01 /December 2014 / Original Instructions
OptistatDry BL4

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
Contents
PREFACE................................................................................................................................. 1
Copyright................................................................................................................................................ 1
Use of this manual ................................................................................................................................. 1
Other documents supplied with the system ........................................................................................... 1
Disclaimers............................................................................................................................................. 3
Customer support................................................................................................................................... 4
Health and safety information ................................................................................................................ 4
Acknowledgements................................................................................................................................ 5
Acronyms ............................................................................................................................................... 5
Certification compliance statements ...................................................................................................... 6
1HEALTH AND SAFETY....................................................................................................... 7
1.1 Safety symbols used in this manual............................................................................. 7
1.2 Safety requirements..................................................................................................... 8
1.3 Warnings ..................................................................................................................... 8
1.4 Temperature and voltage limits.................................................................................... 9
1.5 Service and repair........................................................................................................ 9
1.6 Restrictions on use...................................................................................................... 9
1.7 Safety features............................................................................................................. 9
1.7.1 Compressor and cold head....................................................................................................... 9
1.7.2 MercuryiTC temperature controller......................................................................................... 10
1.7.3 Cryostat................................................................................................................................... 10
1.8 Disposal and recycling instructions............................................................................ 11
2INTRODUCTION................................................................................................................ 12
2.1 Description of the OptistatDry BL4 system................................................................. 13
2.2 OptistatDry BL4 cryostat components........................................................................ 15
3UNPACKING AND ASSEMBLY........................................................................................ 17
3.1 Siting considerations.................................................................................................. 18

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
3.2 Unpacking.................................................................................................................. 20
3.3 Fitting the cryostat to the vertical support stand......................................................... 21
3.3.1 Define the window height........................................................................................................22
3.3.2 Move the support cradle to the correct height........................................................................23
3.3.3 Fit the cryostat to the vertical support stand........................................................................... 25
3.4 Cryostat height adjustments....................................................................................... 29
3.4.1 Minor adjustments ..................................................................................................................29
3.4.2 Major adjustments ..................................................................................................................30
3.5 Fitting cryostat radial restraints.................................................................................. 31
3.6 Making the compressor ready.................................................................................... 35
3.7 Connect helium gas lines to cold head....................................................................... 36
3.8 Temperature monitoring and control system.............................................................. 39
3.8.1 Set up the temperature controller...........................................................................................39
3.8.2 Connect the temperature controller........................................................................................ 40
4FIRST TEST ...................................................................................................................... 41
4.1 Introduction................................................................................................................ 41
4.2 Vent the cryostat and remove the sorption pump....................................................... 42
4.3 Condition the sorption pump and close up system..................................................... 43
4.4 Pump out the cryostat................................................................................................ 45
4.5 Start up the compressor............................................................................................. 46
4.5.1 Run the system to base temperature .....................................................................................46
4.6 Control the sample region at 300K............................................................................. 47
4.7 Warm the cryostat to room temperature..................................................................... 47
4.8 Using the MercuryiTC temperature controller............................................................. 47
4.8.1 Powering up the MercuryiTC.................................................................................................. 47
4.8.2 Temperature control above base temperature.......................................................................48
4.9 Fit optical windows..................................................................................................... 49
5NORMAL OPERATION ..................................................................................................... 51
5.1 Introduction to normal operation ................................................................................ 51

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
5.2 Fitting and removing the standard sample holder....................................................... 53
5.2.1 Electrical connection via the DRYLX20 connector.................................................................55
5.3 Fitting and removing the optical tail for greater access............................................... 56
5.4 Fitting the puck sample holder................................................................................... 58
5.5 Condition the sorption pump and close up system..................................................... 59
5.6 Pump out the cryostat................................................................................................ 59
5.7 Start up the compressor............................................................................................. 60
5.8 Control sample temperature....................................................................................... 60
5.9 Warm up for sample change...................................................................................... 60
6MAINTENANCE AND SERVICING.................................................................................... 61
6.1 Introduction................................................................................................................ 61
6.2 Maintenance Schedule .............................................................................................. 61
6.3 Cryostat O-rings......................................................................................................... 61
6.4 Anti-vibration mounts and radial restraints................................................................. 61
6.5 GM cold head and compressor maintenance............................................................. 62
7TROUBLESHOOTING....................................................................................................... 63
Appendix A TECHNICAL DATA............................................................................................ 65
A1 Physical specifications of cryostat.................................................................................................. 65
A2 Physical specifications of cryostat fitted to optional vertical support stand....................................65
A3 Wiring of 15 way micro D connector to sample heater and thermometer ......................................66
A4 Wiring of optional 21 way micro D connector to DRYLX20............................................................ 67
Appendix B SAMPLE PUCK OPTIONS ................................................................................ 68
Customer support.................................................................................................................. 70

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
Page 1
PREFACE
Welcome to the System Manual for the OptistatDry BL4 cryogenic system.
Copyright
The copyright of this document belongs to Oxford Instruments Nanotechnology Tools Ltd, 2014.
Oxford Instruments Nanotechnology Tools Ltd, trading as Oxford Instruments Omicron
NanoScience gives you permission to make hard copies of this system manual for your
organisation’s internal use in connection with your OptistatDry BL4 system, provided that the
integrity of the manual is maintained and this copyright notice is reproduced. Other than as
permitted above, you may not reproduce or transmit any part of this document, electronically or
mechanically, without the prior written permission of Oxford Instruments Omicron NanoScience.
Use of this manual
This System Manual and accompanying documents supplied with the system provide all the
information necessary for the safe and proper installation, operation and servicing of the
OptistatDry BL4.
Chapters 1 to 5 of this manual provide essential information that must be read and understood
before operating the OptistatDRY BL4 for the first time.
Other documents supplied with the system
The following documents are supplied (hard copy and/or CD) with the OptistatDry BL4 system
depending on options ordered:
Safety Matters
Practical Cryogenics
OptistatDry BL4 Safety Sheet
Unpacking Sheet
Operation Quick Start sheet
SHI SRDK-101D-HC4A2 Cryocooler Operation Manual (CD32ZZ-421A) - for
OptistatDry BL4A air cooled option

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SHI SRDK-101D-HC4E2 Cryocooler Operation Manual (CD32ZZ-422A) - for
OptistatDry BL4W water cooled option
SHI HC-4A and HC-4A2 Zephyr Air-Cooled Helium Compressors Technical Manual
(267825A) - for OptistatDry BL4A air cooled option
SHI HC-4E1 and HC-4E2 Helium Compressors Technical Manual (267318A) - for
OptistatDry BL4W water cooled option
SHI RDK-101D 4K Cold Head Technical Instruction (CD32ZZ-108)
MercuryiTC Temperature Controller Manual UMC0071 (if temperature controller option
ordered)
H4-600 or H4-601 Pumping Kit Manual (if vacuum pump option ordered)
Thermometer calibration data
System Test Data Sheet
Intended users
Users of this product must have received adequate training on its safe and effective use before
attempting to work with the equipment. Please contact Oxford Instruments Omicron
NanoScience for information on training requirements and training courses that are available.
Training requirements vary from country to country. Users must ensure that training is given in
accordance with all applicable local laws and regulations.
If any user of the equipment has not been directly trained by Oxford Instruments Omicron
NanoScience, ensure that they understand the safety issues associated with the equipment,
and that they consult relevant personnel for guidance when operating the equipment.
Statement of intended use of the OptistatDry BL4
The OptistatDry BL4 has been designed for use in a laboratory environment. The equipment
has been designed to operate within the process parameter limits that are outlined in this
manual.
The OptistatDry BL4 is intended to be installed, used and operated only for the purpose for
which it was designed, and only in accordance with the instructions given in this manual and
other accompanying documents. Nothing stated in this manual reduces the responsibilities of
users to exercise sound judgement and best practice.

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
Page 3
It is the user's responsibility to ensure the system is operated in a safe manner. Consideration
must be made for all aspects of the system's life-cycle including, handling, installation, normal
operation, maintenance, dismantling, decontamination and disposal. It is the user's
responsibility to complete suitable risk assessments, to determine the magnitude of hazards.
The installation, use and operation of the OptistatDry BL4 are subject to laws in the
jurisdictions in which the equipment is installed and in use. Users must install, use and operate
the equipment only in such ways that do not conflict with said applicable laws and regulations.
If the equipment is not installed, used, maintained, refurbished, modified and upgraded as
specified by the manufacturer, then the protection it provides could be impaired. Any resultant
non-compliance, damage, or personal injury would be the fault of the owner or user.
Use of the equipment for purposes other than those intended and expressly stated by Oxford
Instruments Omicron NanoScience, as well as incorrect use or operation of the equipment, may
relieve Oxford Instruments Omicron NanoScience or its agent of the responsibility for any
resultant non-compliance, damage or injury.
Revision history
This is issue 01 of the OptistatDry BL4 System Manual, as shown in the header at the top of
each page.
The changes made to this document and a summary of previous issues are listed in the table
below. Always use the latest issue of the manual.
Revision
Affected page(s)
Summary of changes
01
All pages
First edition of the OptistatDry BL4
System Manual
Disclaimers
Oxford Instruments Omicron NanoScience assumes no liability for use of any document
supplied with the system if any unauthorised changes to the content or format have been made.
Oxford Instruments Omicron NanoScience´s policy is one of continued improvement. The
Company reserves the right to alter without notice the specification, design or conditions of
supply of any of its products or services. Although every effort has been made to ensure that
the information in this manual and all accompanying documents is accurate and up to date,

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
Page 4
errors may occur. Oxford Instruments Omicron NanoScience shall have no liability arising from
the use of or reliance by any party on the contents of this these documents (including this
manual) and, to the fullest extent permitted by law, excludes all liability for loss or damages
howsoever caused.
All documents (including this manual) are provided without warranty of any kind, either implied
or expressed, including, but not limited to, the implied warranties of merchantability and fitness
for a particular purpose.
Customer support
Oxford Instruments Omicron NanoScience has global customer support facilities that provide a
coordinated response to customer’s queries. All queries are recorded on our support database
and are dealt with as quickly as possible. If we are not able to answer the query immediately,
we will contact you promptly.
Before contacting a customer support facility, please ensure that you have followed the
guidance given in section 7 of this manual.
If you are still unable to resolve the problem, please direct all queries
through your nearest support facility (see last page of this manual).
Health and safety information
There are potential hazards associated with the use of the OptistatDry BL4. Before working
with the product, all personnel must read and become thoroughly familiar with the information
given in section 1. In particular, users must read, understand and strictly observe all:
Warning notices
Caution notices
Safety labels and markings on the equipment
For ease of reference and rapid response in an emergency, the system is supplied with a
document titled “OptistatDry BL4 Safety Sheet” which summarizes the hazards mentioned in
this manual. This Safety Sheet must be kept close to the equipment.
In addition, you should always provide access to the System Manual close to where the system
is used.

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
Page 5
Warranty
The Oxford Instruments customer support warranty provides repair to faults that are a result of
manufacturing defects at Oxford Instruments Omicron NanoScience.
Acknowledgements
All trade names and trademarks that appear in this manual are hereby acknowledged.
Acronyms
The following is a list of acronyms used in this manual.
GM
Gifford-McMahon (refrigerator)
OVC
Outer Vacuum Chamber –the insulating vacuum space around the sample space
and the refrigerator
PID
Proportional, Integral and Derivative –temperature control algorithm terms
RT
Room Temperature
SHI
Sumitomo Heavy Industries
Modifications to the OptistatDry BL4 made without the consent of Oxford Instruments
Omicron NanoScience will void the warranty.

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
Page 6
Certification compliance statements

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
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1 HEALTH AND SAFETY
This chapter describes all health and safety considerations relating to the Oxford Instruments
Omicron NanoScience OptistatDry BL4. Before you attempt to install or operate this equipment
for the first time, please make sure that you are aware of the precautions that you must take to
ensure your own safety.
The following safety precautions must be observed during the operation, service and repair of
this instrument.
Safety procedures are vital to prevent
Serious injury or death
Serious damage to the equipment.
All staff, including cleaning and maintenance staff, who work in the laboratory
must read the Oxford Instruments booklet Safety Matters which accompanies this
manual.
1.1 Safety symbols used in this manual
Symbols are used in this manual to draw your attention to safety procedures that you must
follow to protect yourself or the equipment.
There are two levels of hazard.
A warning indicates a risk to people.
The yellow warning triangle highlights dangers which may cause injury or, in
extreme circumstances, death. The text explains the hazard and the correct
procedure. The warning triangle may be followed by specific symbols and
instructions.
A caution indicates a risk to equipment.
The general caution symbol highlights actions that you must take to prevent
damage to the equipment. The action is explained in the text.

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
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1.2 Safety requirements
It is your responsibility to ensure your own safety, and the safety of the people working around
you.
Before you attempt to install or operate this system, please make sure that you
are aware of all safety precaution listed in this document (the System Manual)
together with the warnings and cautions listed and the operating procedures set
out in the other manuals supplied with the system (e.g. SHI helium compressor
technical manual and MercuryiTC manual).
Warnings and cautions must be followed to ensure your own safety.
The helium compressor, flexible lines and cold head are supplied already
pressurised with pure helium gas at pressures greater than 15 bar (200 psig). Do
not attempt to modify couplings unless you understand the procedures for doing
this safely. Refer to the SHI helium compressor technical manual.
1.3 Warnings
Before you attempt to install or operate this equipment for the first time, please make sure that
you are aware of the precautions that you must take to ensure your own safety.
Before you operate this equipment, you must make sure that you are aware of
the precautions necessary to ensure your own safety. We supply a separate
booklet called Safety Matters with the system. Please read it carefully so that
you fully understand the hazards you may encounter when using cryogenic
equipment.
Oxford Instruments Omicron NanoScience cannot accept responsibility for
damage to the system caused by failure to observe the correct procedures
described in this manual and the other manuals supplied with the system. The
warranty may be affected if the system is misused, or the recommendations in
the manuals are not followed.
The cryostat (including the two side panels and support cradle –see Figure 3)
weighs approximately 23Kg). Two people are required to lift and move it safely.
See section 3.3 of this manual.

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OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
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1.4 Temperature and voltage limits
If you have bought a cryostat and temperature controller together from Oxford Instruments the
temperature controller will have been set up in the factory in order to
prevent you from accidentally exceeding the maximum safe operating temperature of the
cryostat
limit the maximum heater voltage to a safe level.
If you are planning to use an existing temperature controller, or a controller made by another
manufacturer, you should take the same precautions. The recommended values for the heater
voltage limit and the temperature limit are given in the System Test Data Sheet.
If you do not safeguard the system, it is possible to cause serious damage.
1.5 Service and repair
Only qualified and authorised persons must service or repair this equipment.
1.6 Restrictions on use
The equipment is not suitable for use in explosive, flammable or hazardous environments.
The equipment does not provide protection against the ingress of water. The equipment must
be positioned so that it will not be exposed to water ingress.
1.7 Safety features
1.7.1 Compressor and cold head
The compressor is manufactured by Sumitomo (SHI) Cryogenics of America, Inc. and the cold
head is manufactured by Sumitomo Heavy Industries, Ltd.

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Safety features for the cold head and compressor are described in the SHI
documentation supplied with this system. You should ensure that you understand
and comply with all SHI safety warnings and cautions.
1.7.2 MercuryiTC temperature controller
OptistatDry BL4 systems will normally be supplied with a MercuryiTC temperature controller.
Safety features for the MercuryiTC temperature controller are described in the
manual supplied with this system. You should ensure that you understand and
comply with all safety warnings and cautions.
1.7.3 Cryostat
There is a single over-pressure relief plate on the front of the cryostat (see Figure 1 and Figure
3). It prevents the internal pressure in the cryostat from rising significantly above atmospheric
pressure by lifting to allow gas to vent. Note that the relief plate will not lift during normal
operation of the system. Four restoring springs provide the force required to re-seal the relief
plate automatically when the pressure drops.
Figure 1 OptistatDry BL4 pressure relief plate
Do not modify or tamper with this safety feature in any way. Ensure that nothing
can restrict the movement of the plate.

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1.8 Disposal and recycling instructions
Before disposing of this equipment, it is important to check with the appropriate local
organisations to obtain advice on local rules and regulations about disposal and recycling.
You must contact Oxford Instruments Omicron NanoScience Customer Support (giving full
product details) before any disposal begins.

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2 INTRODUCTION
The OptistatDry systems comprise a range of compact cryostats with optical access cooled by
a closed cycle refrigerator. These systems are capable of cooling samples to helium
temperatures without the need for liquid cryogens. This provides significant benefits in terms of
ease of use and running costs. Cooling of samples becomes a very straightforward, reliable
process that requires no cryogenic infrastructure. The OptistatDry is designed to be
Versatile
Upgradeable
Simple to use.
and to provide
Optical excellence.
The OptistatDry BL4 (bottom loading) system provides a temperature controlled sample-in-
vacuum measurement environment within a cryofree cryostat (i.e. a cryostat that is cooled by a
mechanical refrigerator as opposed to liquid cryogens). The system enables optical and
electrical measurements to be carried out on the user’s sample.
The cooling source for the cryostat is a two-stage Gifford McMahon (GM) refrigerator supplied
by Sumitomo Heavy Industries (the RDK-101D cold head and HC-4 compressor). The sample
cools through a direct conductive thermal path to the second stage of the refrigerator. The first
stage of the refrigerator is used to cool a radiation shield which acts to minimise the radiative
heat load to the second stage of the refrigerator and to the sample region.
The lower tail section of the cryostat (the window block) has been designed so that it is easy to
remove and replace the sample mounting platform once the cryostat has been warmed to room
temperature (cooler switched off) and the cryostat vacuum let up to atmospheric pressure. The
sample mounting platform has two main variants. The first is a nickel plated copper blade
platform suited to optical experiments with no or limited electrical measurement requirements.
The second is a circuit board style platform (puck) suited to combined optical/electrical transport
experiments.

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OptistatDry BL4
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2.1 Description of the OptistatDry BL4 system
Figure 2 shows a schematic diagram of the complete OptistatDry BL4 system. Note that some
components are optional and may not be supplied with your system. The main components are:
1 The cryostat, consisting of
the heat exchanger, which is fitted with a temperature sensor and heater –internal wiring
from hermetic 15 way micro D connector on the OVC. The sample mounting platform
(copper blade or puck) can be removed from the heat exchanger when you need to change
samples.
the cold head (to which the heat exchanger is thermally attached)
the outer vacuum chamber (OVC) and radiation shields that isolate the sample from the
room temperature surroundings. The radiation shield is fitted with an activated charcoal
sorption pump which helps maintain the cryostat vacuum when the system is in operation
the optical window block which allows optical and physical access to the sample mounting
region
experimental wiring loom (optional extra) –internal wiring from hermetic 21 way micro D
connector on the OVC to the sample mounting region connector.
external cable for the experimental wiring loom (optional extra) –plugs into the hermetic 21
way micro D connector on the OVC and terminates with free ending wires so that the cable
can be easily adapted to suit your experimental requirements.
2 The optional cryostat stand (used to support the cryostat and enable it to be mounted
securely to an optical bench), consisting of
a pair of side panels
a support cradle with anti-vibration mounts
four radial restraints
3 The cryocooler, consisting of
the compressor (which supplies the compressed He gas to the cold head)
the cold head

System Manual
Issue 01 /December 2014 / UMC0068
OptistatDry BL4
©2014 Oxford Instruments Omicron NanoScience. All rights reserved.
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the return and supply high pressure gas lines (between the cold head and compressor).
the power cable between the cold head and the compressor
4 The temperature controller (optional extra), which monitors and controls the heating and
thermometry for the heat exchanger.
5 The temperature control cable (optional extra), which links the temperature controller to the
temperature sensor and heater at the heat exchanger via the hermetic 15 way micro D
connector on the OVC.
Figure 2 Schematic diagram of OptistatDry BL4 system
The sample space and radiation shields are thermally isolated from the room temperature
surroundings by the OVC. The OVC must be pumped to a high vacuum using an external
pumping system before the cryostat is cooled down.
During use, the cryostat vacuum is maintained using an internal sorption pump (with activated
charcoal as the adsorption material). The sorption pump is an integral part of the removable
radiation shield inside the window block. The refrigerator maintains the sorption pump
temperature at about 40K (or colder) even when the sample region is controlled at 300K.
Consequently, the pumping efficiency is maintained at all times and there is no need to have the
OVC continuously connected to an external pumping system.
Temperature controller (option)
Compressor
(Return) High pressure gas line
(Supply) High pressure gas line
To vacuum
pump
Cold head power cable
User wiring (option)
21 way D
15 way D
Cryostat and integral cold head

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Page 15
2.2 OptistatDry BL4 cryostat components
Figure 3 (front view) and Figure 4 (rear view) identify the main components of the OptistatDry
BL4 cryostat assembly. The front/rear convention is defined as follows:
The front of the cryostat provides access for sample changing.
The compressed gas lines are attached to the cold head at the rear.
Figure 3 OptistatDry BL4 front view
Pressure relief
plate
Side panel (left)
Side panel (right)
Outer window
assembly
Cold head dust
cover
Sample access plate
Optical window block

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Figure 4 OptistatDry BL4 rear view
Note that the front-facing edges of the side panels are wider than those at the rear. Figure 3
and Figure 4 are consistently labelled to show that the right (or left) side panel is on the right
(or left) as viewed from the front.
Cold head
pressure relief
valve
NW16 Vacuum
pumping port
and valve
Support cradle (includes anti-
vibration mounts)
Cold head power
connector
SUPPLY High pressure
He gas line connection
RETURN High pressure
He gas line connection
Side panel (right)
Side panel (left)
Electrical connectors:
15 way D for heater and sensor of heat
exchanger
21 way D for experimental wiring loom (optional)
Anti-vibration mounts (4)
Feet for mounting
cryostat to optical bench
(with slots for imperial
and metric spacings)
Main OVC body
Radial restraints (4)
L shaped support
brackets (4)
T slot