Abstract
Recently, high energy radiation has been used for medical diagnosis and treatment, and the standard dosimetry is defined as air kerma and absorbed dose to water. Because human’s body contains 70% water, so it can be assumed that body is water equivalent. To measure the absorbed dose to water in medical radiation oncology, an ion chamber calibrated with colbat-60 irradiation is used together with a phantom to measure the electric charge after being exposed to high energy radiation, and then according to AAPM No.21 or No.51,the human’s body dose can be calculated. Many research workers have investigated the glow curve and dynamic of CVD diamond film fabricated with chemical vapour deposition methods(CVD method), and they have also used computer code for glow curve fitting and identification of the light source interference from radiation. In practice, the glow curve must be analyzed by computer, in order to obtain the dose. This work is to study CVD diamond as a tool for radiation dosimetry, and to find the reading modular similar to TLD which can then be used in laboratories. The main component of CVD diamond film is carbon, its atomic number is 6 which is close the mean atomic number of 7.4 for water, it can be used as a tissue equivalent material, and is convenient to measure absorbed dose to water. Results of experiment show that the difference between absolute dose measured and dose profile obtained is about ±10%. The CVD diamond is a practical material for high-energy radiation measurements.