Cryostat Thermalization Plate for RF Wireline Heat Dissipation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cryocooled devices face challenges in minimizing thermal power dissipation due to physical connections, particularly with metallic wires, which affect device performance and integrity at cryogenic temperatures, especially when handling high-bandwidth RF signals.

Innovation Solution

The implementation of an Insulated Metal Substrate (IMS) thermalization plate within a cryostat system, which includes a high thermal conductivity layer, a thin dielectric insulating layer, and conductive circuitry layers, effectively redirects and dissipates heat away from the cryogenic sample chamber, maintaining low attenuation and impedance matching for high-frequency signals.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If metallic wires are used for physical connections between cryocooled device and external system, then electrical conductivity is improved, but thermal power dissipation increases

Engineering Contradiction:
Improveelectrical conductivityVSAvoidthermal power dissipation
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The wireline connection is divided into multiple segments with different thermal properties. The first portion uses a material with low thermal conductivity to minimize heat flow from room temperature, while the second portion uses a material with high thermal conductivity to efficiently conduct RF signals at cryogenic temperatures. This segmentation allows each segment to be optimized for its specific function.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different portions of the wireline have different thermal and electrical properties optimized for their local requirements. The first portion (at higher temperatures) has low thermal conductivity to reduce heat load, while the second portion (at cryogenic temperatures) has high electrical conductivity for signal transmission. The connection point between these portions is thermally anchored to the cryocooled stage.

Inventive Principle:
Principle #3Local quality

2Loss of energy

If wire cross-sectional area is reduced to lower thermal conduction, then thermal power dissipation is reduced, but electrical conductivity deteriorates

Engineering Contradiction:
Improvethermal power dissipationVSAvoidelectrical conductivity
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The wireline is segmented into two portions with different cross-sectional areas and materials. The first portion has a smaller cross-sectional area with low thermal conductivity material to minimize heat flow. The second portion has optimized dimensions for high electrical conductivity at cryogenic temperatures. This segmentation resolves the contradiction by allowing each segment to have dimensions optimized for its primary function.

Inventive Principle:
Principle #1Segmentation

3Temperature

If thermalization is implemented to reduce heat load on device, then device temperature stability is improved, but device performance deteriorates due to thermal connection to low temperature stage

Engineering Contradiction:
Improvetemperature stabilityVSAvoiddevice performance
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The wireline is segmented so that only the necessary portion is thermally anchored to the cryocooled stage. The first portion remains thermally isolated to minimize heat load, while the second portion provides the necessary thermal anchoring for RF signal transmission. This optimized segmentation maintains device temperature stability without excessive thermal connection that would degrade performance.

Inventive Principle:
Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution enables efficient thermalization of wirelines, reducing heat load on cryogenic samples, maintaining high-performance detection efficiency for SNSPDs and SSPDs, and facilitating industrialization and mass production of cryostat systems for weak and high-frequency signal transmission.

Implementation Method 1

The implementation of an Insulated Metal Substrate (IMS) thermalization plate within a cryostat system, which includes a high thermal conductivity layer, a thin dielectric insulating layer, and conductive circuitry layers, effectively redirects and dissipates heat away from the cryogenic sample chamber

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

a thin dielectric insulating layer

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3109575B1Apparatus and method for cryocooled devices thermalization with RF electrical signals
Publication Date: 2018.10.10 ID QUANTIQUE SA
  • EP3109575B1 patent drawingFigure 1a~1b
  • EP3109575B1 patent drawingFigure 2a~2b
  • EP3109575B1 patent drawingFigure 3

AI summary

Cryogenic device comprising at least two chambers (120, 130) at two different temperatures, a first chamber (130) at a first temperature T1 accommodating a sample (131), and a second chamber (120) at a second temperature T2 greater than T1 and being adapted to accommodate a cooling device (170), said cooling device being adapted to cool wirelines (150, 160) connecting said sample to an external element detector, characterized in that said cooling device is a thermalization plate comprising at least one wire-guide having an input (105) for plugging a wire line (160) connected to the sample and an output (106) for plugging a wire line connected to said external element, said wire-guide being thermally connected to the first chamber.