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Equipment Cleaning to Minimize Particle Deposition
Published in R. P. Donovan, Particle Control for Semiconductor Manufacturing, 2018
A commercially available in situ particle detector is the High-Yield Technology Particle Flux Detector. This instrument is similar to the particle-detection apparatus of a standard light scattering optical particle counter, but it has a novel design to increase the area that is sensitive to particles. A diode laser light beam is reflected back and forth between two mirrors to create a sheet of light. Particles that pass through the light beam scatter light out of the plane of the sheet. The scattered light is focused on detectors by mirrors. The amount of scattered light is proportional to the particle size. An electrical feedthrough provides power to the instrument when it is mounted inside equipment, and passes signals from the instrument to external signal processing hardware. The minimum particle size detected is about 0.5 μm, although the probability that particles of this size will be detected is quite low. Further details of the design, operation and performance of the High-Yield Technology monitor are discussed in Borden, Baron, and McGinley (1987a, 1987b); Borden and Knodle (1988); Caldow, Pui, and Liu (1987); and Bowling, Larrabee, and Fisher (1988).
Thermostructural Analysis of Large Cryopumping Test Facility
Published in Fusion Science and Technology, 2023
Hemang S. Agravat, Samiran S. Mukherjee, Vishal Gupta, Paresh Panchal, Pratik Nayak, Jyoti Shankar Mishra, Ranjana Gangradey
The GM-type cryocooler is mounted on the end flange of the cryochamber and will be used to cool down the panels during the first and second stages. The LN2 bath has a 1/2-in. inlet pipe for the inflow of LN2 and a 1-in. outlet pipe for the outflow of gaseous nitrogen from the LN2 bath. These pipes will be sealed with the help of Wilson couplings connected to two flexible bellows, which allows for contraction and expansion of the pipes during the cooldown, baking, and warm-up operations. The end flange consists of several ports for the turbomolecular pump (TMP), roots-rotary vacuum pump, and the electrical feedthrough and LN2 feedthrough pipes. The test dome chamber (Fig. 1) is used to test and evaluate the pumping speed of the pump for the different gases. The test dome is designed as per AVS standards.14 The overall dimensions of the LCTF are described in Table II. A complete three-dimensional (3-D) computer-aided design (CAD) modeling was carried out using CATIA V5-6 2018 software.
Development of Bunching System for High Intensity Cyclotron at CIAE
Published in Journal of Nuclear Science and Technology, 2022
Pengzhan Li, Tianjue Zhang, Xianlu Jia, Bin Ji, Guofang Song, Ming Li, Junyi Wei
The buncher, 0.76 m away from the inflector, is installed in the injection line of CYCIAE-10. The frequency of RF system is 70.5 MHz. It is a typical double gap cylinder buncher with gap distance of , where β and λ denote the ratio of particle velocity to the speed of light in vacuum and the RF wavelength, respectively. The length of two bunching gaps is decided as 15.8 mm. Sinusoidal voltage is adopted and applied on the central electrode of the buncher through vacuum feedthrough to get the roughest approximation of sawtooth. To achieve an acceptable transit time factor, the buncher inner radius should not be made too large [13]. In this case, the inner radius of the buncher electrode is designed as 15 mm, which also matches the beam envelope in the injection line. The buncher gap is initially set as 5 mm.
DLC (H) coated 13Cr SMSS by high-pulsed power CVD technique
Published in Surface Engineering, 2021
Yukun Zhang, Dongxu Chen, Hongyun Deng, Jilong Qi, Kaice Zhang, Zhe Lv, Tao Zhang, Peng Gao, Yanwen Zhou
The chamber was pumped down to a basic pressure of 1 × 10−3 Pa, and then Ar gas was refilled to a pressure of 2 Pa. The samples in the metal cage were bombarded by Ar ions for 40 min at a voltage of 2800 V to remove surface contaminants. C2H2 gas was introduced into the chamber at an Ar/C2H2 flow ratio of 3:1 at a steady pressure of 2 Pa. The pulsed current, frequency, and width were set at 200 A, 1200 Hz, and 20 μs, respectively. The influence of the plasma energy on the structure and performance of the DLC films was investigated by varying high-pulsed voltages. The substrate temperature was set at 100°C, which was monitored by a feedthrough thermocouple wire near the surface of the samples. The specific parameters are listed in Table 1.