Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5499033 | Radiation Physics and Chemistry | 2017 | 5 Pages |
Abstract
In this work, the initial interface trap density (Nit) to examine device compability for microelectronics and then the Co-60 gamma irradiation responses of Al/HfSiO4/p-Si/Al (MOS) capacitors were investigated in various dose ranges up to 70Â Gy. Pre-irradiation response of the devices was evaluated from high frequency (HF) and low frequency (LF) capacitance method and the Nit was calculated as 9.91 Ã 1011Â cmâ2 which shows that the HfSiO4/p-Si interface quality is convenient for microelectronics applications. The irradiation responses of the devices were carried out from flat-band and mid-gap voltage shifts obtained from stretch of capacitance characteristics prior to and after irradiation. The results show that the flat band voltages very slightly shifted to positive voltage values demonstrating the enhancement of negative charge trapping in device structure. The sensitivity of the Al/HfSiO4/p-Si/Al MOS capacitors was found to be 4.41Â mV/Gy for 300Â nm-thick HfSiO4 gate dielectrics. This value approximately 6.5 times smaller compared to the same thickness conventional SiO2 based MOS devices. Therefore, HfSiO4 exhibits crucial irradiation tolerance in gamma irradiation environment. Consequently, HfSiO4 dielectrics may have significant usage for microelectronic technology as a radiation hard material where radiation field exists such as in space applications.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Radiation
Authors
R. Lok, S. Kaya, H. Karacali, E. Yilmaz,