Low temperature experimental equipment for 10nm 4K liquid helium ultra-low temperature system

1、 Overview:

System composition:

The system consists of a helium refrigerator, helium compressor, water cooler, vacuum pump assembly, temperature sensor, temperature controller, vacuum chamber, KF25 vacuum suction port, as well as accessories such as refrigerator bracket, sample stage, and sample card.Low temperature experimental equipment for 10nm 4K liquid helium ultra-low temperature system

Product Features:

1. Cooling capacity: primary cooling 7W@45K Secondary refrigeration 1.0W@4K The required electricity is 380V, 50Hz.

2. Work pressure:<2 × 10^-4During normal production, the leak will be detected by a helium mass spectrometer leak detector, and the vacuum degree can reach 10^-4Pa， (Optional 10)^-6Pa) depends on the ultimate vacuum of the pump.

3. Temperature monitoring: Set up a temperature measurement point at the sample stage to monitor and display the temperature at the sample location. Temperature measurement accuracy ± 0.01K.

4. Sample cooling and heating time: The cooling time to 4K is less than 2.2 hours (increasing the chamber will prolong the cooling time), and the time to return to room temperature under vacuum after cooling shutdown is less than 3 hours. The device uses a closed cycle refrigeration mechanism without liquid helium for cooling, with a cooling capacity of 4K@1.0W The time required to cool down to 70K without load is 60 minutes. After installing the load, considering the cooling of the load and related supporting devices, the cooling time will be correspondingly extended. However, based on experience, the cooling time is approximately 1.2 hours, which meets the experimental requirements.

5. Integrated control system: controls the operation and safety feedback functions of the vacuum system and refrigeration unit. Can set and display work target parameters and system working status, with feedback safety control function.Low temperature experimental equipment for 10nm 4K liquid helium ultra-low temperature system

Technical Indicators:

Vibration intensity: ＜ 10nm

Temperature range: 4.5K-325K (-269.15 ℃ -51 ℃ above zero)

Temperature measurement accuracy: 0.01 ℃

真 空 度： 10^-4pa

Optical windows: 2 (customizable)

Window material: fused silica

Output electrodes: 8 pieces

2、 Operation process

1: Install the corresponding fixtures according to the required experiments. After installation, complete the system components according to the drawings.

2: Use a molecular pump assembly to connect the molecular pump pumping port of the molecular pump assembly and the vacuum pumping port of KF25 in the vacuum chamber with a welded bellows. Open the high vacuum baffle valve on the bellows, open the molecular pump assembly, and reduce the vacuum degree in the system to below 2X10^-4Pa， Close the baffle valve and remove the corrugated pipe (if it is not inconvenient during the experiment, it can be left untouched);

3: Connect the temperature controller, turn on the compressor, and cool down the system to below 4K. Display the nearby temperature and the temperature at the cold head on the temperature controller.

4: After the test is completed, turn off the compressor and wait for the system to automatically heat up.

thermal simulation analysis

When the temperature drops to 4K, the power of the refrigeration unit is 1.2W. At this time, thermal simulation analysis is conducted on the entire environment, and the specific analysis results are shown in the following figure.

According to the thermal simulation results, the temperature is uniform and consistent at 4.2K.

More indicators: For more information, please contact Jinzhengmao Technology