The Effect of Si/SiO2 Interface on the Electrical Properties of MOS Device with Nano Layer Silicon Dioxide Grown by Induced Laser Oxidation


In this work a MOS device was fabricated with nano dioxide layer on silicon using a laser induced oxidation technique, at 600oC temperature for different times oxidation (5-20) min.FTIR spectrums were studied and analyzed for the Si (111) substrate, the Si/SiO2 interface and the SiO2 layer. The results gave a characteristic sharp peak presence at the wave number (1079 cm-1) corresponding to the level of elongation vibration (Si-O-Si) which consists the required oxide.The electrical measurement results show the response of the MOS device for the (C-V) and (I-V) characteristics. The capacity was inhomogeneous at the interface between insulator and semiconductor because of the (ac) signal harmony, as an extra-capacity created depending on the frequency, while it does not appear at frequency (f >5kHz). This determines the nature of the electronic response of the device. The different times for the oxide configuration gives a different value for the capacity that's where the capacity increases with the time of laser induction oxidation increase. The oxide thickness has an inverse relationship with the time of laser induction of the oxidation.The (I-V) characteristics show the MOS devices fabricated with oxidation time at (5,10) min has leakage current started after 0.6 volt, where the devices which oxidized for 15 min has leakage current at 0.4 volt, but the leakage current begun at 0.2 volt for the devices with 20 min oxidation time.