HFSIO4 metal oksit yarıiletken (MOS) kapasitörlerin elektriksel karakterizasyonu ve gamma radyasyonu duyarlılıkları

The smallest pollution that will form or remain on the silicon wafers directly affects the performance of devices produced. Therefore, in the scope of the study, first RCA wafer cleaning procedure was applied in three stages. The first organic cleaning was intended to remove possible organic contaminants at the first stage with a 5: 1: 1 H2O: H2O2: NH4OH mixture. The second stege was ionic cleaning the purpose of this process was to remove the ionic and heavy metal impurities that may form on the Si wafers by a mixture of 6: 1: 1 H2O: H2O2: HCl. In the third and final stage, a certain amount of oxide layer may grow spontaneously on the Si wafers. The diluted HF solutionwas used to remove the oxide. HfSiO4 thin films were fabricated by RF sputtering system with the power of 200 W, 250W, 300W onto p-type (100) Si substrate and then annealed at 500 0C, 750, 0C 1000 0C in Nitrogen environment for 40 minutes. . In addition, the produced thin films were transformed to MOS capacitors. The electrical characteristics of the capacitors were determined by C–V and G/ω–V measurements for several frequencies from 50 kHz to 1 MHz. The C–V characteristics of the MOS capacitors fabricated at 300 W and annealed at 750 C demonstrate better behavior compared to others MOS capacitors. So, to study their susceptibility to radiation, the capacitors were irradiated with a GAMMACELL 220 Co-60 radioactive gamma source up to 70 Gy at a rate of 0.0055 Gy / s. The 1 MHz C-V measurements of the samples were taken at each irradiation step and the radiation sensitivitiy of the devices were examined using flat band and midgap voltage shifts.