THE CURRENT-VOLTAGE CHARACTERISTICS OVER THE MEASUREMENT TEMPERATURE OF 60-400 K IN THE Au/Ti/n-GaAs CONTACTS WITH HIGH DIELECTRIC HfO2 INTERFACIAL LAYER
[ X ]
Tarih
2019
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
World Scientific Publ Co Pte Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The Au/Ti/HfO2/n-GaAs metal/insulating layer/semiconductor structures have been fabricated using standard thermal atomic layer deposition. We experimentally showed whether or not the HfO2 interfacial layer grown on the n-GaAs wafer modifies the barrier height (BH) of the device at the room temperature. Besides, we investigated the measurement based on temperature dependence of the device parameters from the current-voltage (I-V) characteristics of the diode in 60-400 K range with steps of 10 K. The X-ray photoelectron spectroscopy (XPS) have been carried out to characterize the surfaces of both n-GaAs wafer and HfO2 thin films. The series resistance value from the temperature-dependent I-V characteristics decreased with decreasing temperature, which is a desired positive result for the devices developed from the MOS capacitor. The BH value of 0.94 eV (300 K) has been obtained for the device with the HfO2 layer which is a higher value than the value of 0.77 eV (300 K) of the device without HfO2 layer. Therefore, we can say that the HfO2 thin layer at the metal/GaAs interface can also be used for the BH modification as a gate insulator for GaAs MOS capacitor and MOSFETs. When the temperature-dependent I-V characteristics at low temperatures have been considered, it has been observed that the current prefers to flow through the lowest BHs due to the BH inhomogeneities.
Açıklama
Anahtar Kelimeler
HfO2 thin layer, Atomic layer deposition (ALD), Schottky barrier modification, metal-insulating layer-semiconductor structures, barrier height inhomogeneous, temperature-dependent device parameters, Gauss distribution
Kaynak
Surface Review and Letters
WoS Q Değeri
Q4
Scopus Q Değeri
Q3
Cilt
26
Sayı
8
