PCVD technique is used to develop lab growing diamonds. In this process, carbon plate is placed in a selected chamber at under high temperature and high pressure. The temperature is used in this technique is 700 – 1200 °C and carbon rich gases are filled in the chamber. These gases are ionized in the form of plasma. Plasma is deposited layer by layer and this process will take approximate 300 – 600 hours. After this carbon is produced.
The method for producing diamond includes positioning diamond in a holder such that a thermal contact is made with a side surface of the diamond adjacent to an edge of a growth surface of the diamond, measuring temperature of the growth surface of the diamond to generate temperature measurements, controlling temperature of the growth surface based upon the temperature measurements and growing single crystal diamond by microwave plasma chemical vapour deposition on the growth surface, wherein the growth rate of the diamond is greater than 1 micrometer per hour. In this whole process temperature plays very important role. We need to measure the temperature of the target diamond rather than the plasma.
Temperature Measurement by Infrared Pyrometers
A non-contact temperature measurement device is positioned to measure the temperature of the diamond across the grown surface of the diamond. The pyrometer is mounted on a glass window of a chamber to read the temperature of target diamond. The challenging part of the application is Plasma emits IR energy at specific wavelengths and we need to measure consistent temperature of the target through the plasma. AST offers Non-contact type IR based Pyrometer which works in selected wavelength where plasma is transparent.
- Temperature Range – 350°C to 1800°C
- Fast response time in millisecond
- Laser sighting
- Connectivity via USB 2.0, Bluetooth V2.0 and RS-232 or RS-485 Serial interface
- High accuracy
- Measure the temperature of target through plasma at specific wavelength