Helium mass spectrometry leak detection for long crystal furnace
Microwave plasma chemical vapor deposition is currently the preferred method internationally for the preparation of high-quality diamond films.
The crystal growth furnace device is a device that transmits microwaves generated by a microwave generator through a waveguide transmission system into a reactor, and introduces a mixture of methane and hydrogen gas. Under the excitation of microwaves, a glow discharge is generated in the reaction chamber, causing the molecules of the reaction gas to ionize and generate plasma, which deposits diamond films on a substrate.
Usually, in the process of diamond synthesis using a long crystal furnace equipment, if there is leakage in the equipment, impurities will be added to the synthesized diamond, affecting the quality of the diamond. The general leakage rate requirement is 1E-10 Pa m3/s (1E-9 mbar l/s). The traditional leak detection method cannot meet the requirement of rapid quantitative positioning of equipment for leak detection.
To solve this problem, it is recommended that the customer purchase a helium mass spectrometer leak detector and use the vacuum method to detect leaks in the long crystal furnace, with a leakage rate set at 1E-10 Pa m3/s (1E-9 mbar l/s). The operation steps are as follows:
1. Connect the device to the leak detector through a corrugated hose and confirm that the connection is complete;
2. Start the helium mass spectrometer leak detector and enter the standby interface, with a startup time of ≤ 2 minutes;
2. Press the start button, start the vacuum pump through the valve to evacuate, and when the pressure reaches a certain level, the leak detector will start working. At the same time, spray helium gas on the suspected leakage areas of the equipment (cavity, weld, connection). If there is a leak, the leak detector will sound an alarm and display the real-time leak rate;
4. After the inspection is completed, press the stop button of the leak detector and remove the connecting pipeline.
Compared with traditional foam leak detection and differential pressure leak detection, the helium mass spectrometer leak detector can detect a smaller leak rate of 5E-13 Pa m3/s while providing nondestructive leak detection. Helium can be used as a tracer gas to accurately locate and quantify the leak point.
EVP Vacuum Pump Company is a professional manufacturer specializing in the research and development, production, and sales of helium leak detection technology. Currently, it continuously innovates and optimizes, and the entire polishing process strictly follows domestic standards. With modular manufacturing, forward-looking technology, and low maintenance equipment, it continuously provides customers with the best quality service and equipment experience.
(The article comes from the Internet. If reprinting is not allowed, please contact our company to delete it.)