The vacuum interconnection platform and multi-degree-of-freedom cryogenic sample holder of the Institute of Physics, Chinese Academy of Sciences were delivered for use

In May 2019, the vacuum interconnection platform RDC820 and multi-degree-of-freedom cryogenic sample holder designed and manufactured by FERMI INSTRUMENTS (Shanghai) Co., Ltd. completed installation and acceptance at the Institute of Physics, Chinese Academy of Sciences. All indicators met the design requirements and were officially delivered to the research group of Researcher Wu Kehui of the State Key Laboratory of Surface Physics (http://surface.iphy.ac.cn/sf09/index-cn.html).

Researcher Wu Kehui's research group is mainly engaged in the exploration and physical property research of surface and new low-dimensional quantum materials. It uses molecular beam epitaxy (MBE) and scanning tunneling microscopy (STM) to control the structure of materials at the atomic scale, observe the relationship between the structure and physical properties of molecular materials, and obtain a deep understanding of the physical properties of materials.

The angle-resolved photoelectron spectroscopy (ARPES) system built this time is a powerful means to measure the in-situ electronic structure of two-dimensional materials, and it is also complementary to STM. The whole system was designed and built by SPECS of Germany, and two core modules: multi-degree-of-freedom cryogenic sample holder and vacuum interconnection platform were provided by FERMI INSTRUMENTS.

Core Module 1 | Multi-degree-of-freedom cryogenic sample holder

The key equipment required for angle-resolved photoelectron spectroscopy includes: high-brightness light source, electron energy analyzer and multi-degree-of-freedom variable temperature sample holder. With the deepening of condensed matter material physics research, higher requirements are put forward for the resolution of ARPES, and it is hoped that the overall energy resolution of the system will reach the order of 1 meV. The current light source and energy analyzer have achieved a resolution of 1 meV, and the bottleneck lies in the lowest temperature that the sample can reach. In addition, for some low-temperature phase-change materials, such as superconductors, the lowest temperature that can be achieved in the experiment is the key to revealing their novel quantum states.

The multi-degree-of-freedom cryogenic sample holder independently developed by FERMI INSTRUMENTS combines the two conditions of low temperature (liquid helium temperature zone) and multi-degree-of-freedom motion. While providing multiple degrees of freedom (5 degrees of freedom controlled by motors, the sixth degree of freedom is manually controlled), it ensures that the operating temperature is lower than 6K (factory test is 5.6K), and the consumption of liquid helium is much lower than similar products (lowest temperature is less than 1L/h, 10K temperature is less than 0.5L/h).

▲Cryogenic sample holder cooling curve

Core Module 2 | Vacuum Interconnection Platform RDC820

Magnetic coupling linear sample transfer rod is a transfer component that is currently used more in ultra-high vacuum systems, but this type of structure has a very low space utilization rate, and the actual telescopic length is less than 80% of the rod length. In addition, the sample transfer rod plus the subsystem can only be arranged in a straight line, which is greatly restricted in spatial arrangement.

The RDC820 independently developed by FERMI INSTRUMENTS adopts the idea of ultra-high vacuum center. The robot arm can be installed inside a stainless steel chamber with a diameter of 700mm. The stainless steel chamber is equipped with 8 docking flanges as standard. The robot arm can extend 820mm from any opening (starting from the flange surface), and the telescopic ratio is much better than that of ordinary sample transfer rod structure. In addition to rotation and telescopic freedom, the RDC820 robot also has the following freedom:

Lifting, the robot can be lifted and lowered as a whole with the lifting module to adapt to the height difference between different systems. This lifting function can also be used to take/enlarge wafer samples;

Rotation, the robot can achieve 360-degree flipping with the ballistic module to match the sample orientation between different systems;

Sample holder placement, with the standard Flag-Type sample holder, the robot can achieve sample holder placement through a cleverly designed gripping structure;

▲ FERMI RDC820 robotic arm

FERMI INSTRUMENTS is working hard to build an interconnected ecological chain with RDC820 as the core module. At present, RDC820 has more than 20 interconnection cases, including: AFM, STM, MBE, XPS, ARPES, LoadLock, high temperature and high pressure reaction pool, in-situ infrared spectroscopy, glove box, etc. We have also established long-term cooperative relationships with many world-renowned manufacturers to provide users with complete solutions.

Many major scientific discoveries in history have benefited from breakthroughs in experimental conditions or the expansion of research methods. It is hoped that the low-temperature sample holder and vacuum interconnection platform RDC820 delivered by FERMI INSTRUMENTS can help the Institute of Physics of the Chinese Academy of Sciences to push the research in the field of novel materials to a new height.