Silicon diode sensor packages and mounting adapters

Packages and adapters for silicon diodes allow the sensor to be soldered in place, screwed on, bolted down, inserted into a hole, or inserted through a pressure seal in the form of a thermowell. Gold-plated copper bobbins are available in order to heat sink leads. Appendix C: Sensor Packaging and Installation discusses techniques for correctly installing cryogenic temperature sensors. Special packaging is also available—consult Lake Shore for custom orders.

Additional information about Lake Shore sensors and packaging can be found in our Temperature Sensor Selection Guide.

Each sensor package or adapter has been rated for four attributes or characteristics. These ratings give a general idea of how a package will perform and aid in the early decision-making process but are not a substitute for detailed specifications.

temperature-sensor-selection-guide
Silicon diode packages
DT-SD
  • Small package designed primarily for bonding or clamping to a flat surface
  • Indium, silver epoxy, 2850 Stycast® epoxy, or a CO clamp may be used for mounting

Packaging material: Sapphire base with alumina body and lid. 

Molybdenum/manganese metallization on base and lid top with nickel and gold plating. Gold tin solder as hermetic lid seal.

Leads: 2

Lead material: Brazed Kovar

Mass: 30 mg

Limitation: The useful upper-temperature limit of this configuration is 500 K

Temperature probes

Some applications require more protection for your sensors (especially if they have to be immersed in liquid). Cryogenic temperature probes are great for those. Encased in a stainless steel thermowell fixture, the sensor can perform as designed, unaffected by high pressure, and sealed to keep electrical components and wiring protected from fluids and other elements.

  • Stainless steel-encased probes that provide high-reliability sensor performance in a thermowell
  • Sealed to keep electrical components and wiring protected from fluids
  • Ideal for temperature measurements in fluid containers and tanks
  • Hermetic feedthrough at the end 
  • Also beneficial for extended sensor reach in narrow spaces
  • Available in standard lengths up to 28 in (0.7 m) long
  • Custom lengths and configurations are also available

Temperature probe product page

CU-HT

The high-temperature variant of the CU package. Increases the maximum temperature rating of the CU package at the cost of thermal performance.

  • SD packaged sensor indium-soldered into a flat copper bobbin with the leads thermally anchored to that same bobbin
  • HT (high temperature) version is soldered using high temperature (90% Pb, 10% Sn) solder 
  • Can be mounted to any flat surface with a 4-40 or M3 screw

Packaging material: See DT-SD package

Adapter material: Gold-plated copper bobbin (SD package soldered (90% Pb,10% Sn) to CU bobbin and wrapped in Stycast® 2850FT Cat 11 epoxy)

Leads: Four 0.91 m (36 in), phosphor bronze 36 AWG, color-coded Quad-Twist™ leads; Quad-Twist has Polyimide insulation, and the wire ends are tinned with 90/10 PbSn solder

Mass: 1.1 g (including SD package and bobbin, excluding leads)

Limitation: This package allows the maximum sensor temperature of 500 K to be reached. However, the low-temperature performance is reduced with this package variant, requiring immersion in liquid cryogen or vapor to achieve the specified base temperature performance of 1.4 K. Sensors mounted in vacuum may not deliver enough heat-sinking capability to overcome sensor self-heating.

DT-614-UN
  • Low thermal mass
  • Non-magnetic package
  • Insulated substrate for easy mounting to a flat surface
  • Delicate 0.001 in gold lead probe to damage—extreme care required

Sensor material: Alumina base, with metallization: 0.1 µm of molybdenum, 0.2 µm gold

Leads: 2 

Lead type: Gold

Lead polarity: Positive lead on left with the chip up and leads towards user

Mass: 3 mg

Limitation: 1.4 K to 375 K

DT-621-HR

Sensor material: Sensing element is mounted to a platinum disk and covered with a dome of Stycast® 2850 epoxy

Leads: 2

Lead type: Platinum ribbon with tinned 60/40 SnPb solder

Lead polarity: Positive lead is a right-hand ribbon with platinum disk down and leads towards user

Mass: 23 mg

DT-BR

Sensor material: Silicon chip with aluminum metallization on chip contacts

Leads: None

Lead polarity: Positive connection made through bottom of chip; negative connection made on the base pad on top of chip

Mass: 72.7 µg

CO
  • Spring-loaded clamp holds standard SD sensor in contact with the surface of the sample and allows the sensor to be easily changed or replaced
  • Extra clamps are available for frequent relocation of the sensor
  • 4-40 stainless steel screw has a formed shoulder, thus applying correct pressure to the clamp

Packaging material, leads, and lead material:See DT-SD package

Adapter material: Gold-plated copper (nickel strike); spring is ASTM A313 302 Austenitic steel

Mass: 1.8 g (including SD package and clamp)

Limitation: The useful upper-temperature limit of this configuration is 500 K

ET
  • Convenient screw-in package formed by indium soldering a basic SD configuration into a recess in one flat of a hexagonal screw head
  • The head terminates in a standard #6-32 UNC threaded stud allowing the sensor to be threaded into a mounting hole in the sample
  • Note: A light coating of vacuum grease on the threads further enhances the thermal contact between the sensor package and the sample.

Packaging material, leads, and lead material: See DT-SD package

Adapter material: Gold-plated copper #6-32 UNC screw head

Mass: 1.5 g (including SD package and screw head)

Limitation: Indium solder limits the upper useful temperature of this configuration to 420 K

MT
  • Convenient screw-in package formed by indium soldering a basic SD configuration into a recess in a slot in the center of the hexagonal head
  • The head terminates in a 3 mm × 0.5 metric threaded stud allowing the sensor to be screwed into a mounting hole in the sample
  • Note: A light coating of vacuum grease on the threads further enhances the thermal contact between the sensor package and the sample.

Packaging material, leads, and lead material: See DT-SD package

Adapter material: Gold-plated copper metric threaded screw head 3 mm × 0.5 metric

Mass: 1.5 g (including SD package and screw head)

Limitation: Indium solder limits the upper useful temperature of this configuration to 420 K

CY
  • Similar to the DI package, except the bobbin is larger in diameter with a centered mounting hole
  • Relatively large-sized, robust

Packaging material: See DT-SD package

Adapter material: Gold-plated copper bobbin (SD indium-soldered to adapter and wrapped in Stycast® epoxy)

Leads: Two 0.91 m (36 in), 30 AWG color-coded Teflon®-coated leads

Lead material: Stranded copper 

Mass: 4.3 g (Including SD package and bobbin, excluding leads)

Limitation: The epoxy limits the upper useful temperature of this configuration to 400 K

LR
  • With an SD-packaged sensor mounted on a slightly-more-than half-rounded cylinder, this package is designed to be inserted into a 3.2 mm (1/8 in) diameter hole

Packaging material, leads, and lead material: See DT-SD package

Mass: 0.2 g (Including SD package and disk)

Limitation: Indium solder limits the upper useful temperature of this configuration to 420 K

BO
  • SD package is soldered to a mounting block, and the leads are thermally anchored (without epoxy) to the block via a beryllium oxide insert
  • Since leads can be a significant heat path to the sensing element and can lead to measurement errors when incorrectly anchored, this configuration helps maintain the leads at the same temperature as the sensor
  • Can be mounted to any flat surface with a 4-40 or M3 screw

Packaging material: Gold-plated bolt-on copper block with leads thermally anchored to block (SD indium-soldered to adapter)

Leads and lead material: See DT-SD package

Mass: 1.5 g (including SD package and screw head)

Limitation: Indium solder limits the upper useful temperature of this configuration to 420 K

 

DI
  • 2-lead version of the CU
  • Fewer wires to run back to instrumentation, but reduced measurement accuracy due to voltage offset

Packaging material: See DT-SD package

Adapter material: Gold-plated copper bobbin (SD indium-soldered to adapter and wrapped in Stycast® epoxy)

Leads: 0.91 m (36 in), 36 AWG, color-coded, 2-lead ribbon cable with Formvar insulation

Lead material: Phosphor bronze alloy

Mass: 1.1 g (including SD package and bobbin, excluding leads)

Limitation: The Formvar wire insulation limits the upper useful temperature of this configuration to 378 K)

CU

Best general-purpose diode package option, offering an excellent balance of usability and performance. Easier to mount than the SD package using a fastener and includes wires and a built-in thermal anchor, but reduces maximum survivable temperature and increases thermal mass.

  • SD packaged sensor indium-soldered into a flat copper bobbin with the leads thermally anchored to that same bobbin
  • HT (high temperature) version is soldered using high temperature (90% Pb, 10% Sn) solder
  • Can be mounted to any flat surface with a 4-40 or M3 screw

Packaging material: See DT-SD package

Adapter material: Gold-plated copper bobbin (SD package indium-soldered to adapter and wrapped in Stycast® 2850FT Cat 9 epoxy)

Leads: Four 0.91 m (36 in), phosphor bronze 36 AWG, color-coded Quad-Lead™ leads

Mass: 1.1 g (including SD package and bobbin, excluding leads)

Temperature range: The epoxy limits the useful upper temperature of this configuration to 420 K. Self-heating limits the useful minimum temperature, and sensor mounting best practices are required to achieve the 1.4 K minimum temperature.