Investigation of temperature dependent negative capacitance in the forward bias C-V characteristics of (Au/Ti)/Al2O3/n-GaAs Schottky barrier diodes (SBDs). (January 2019)

• Record Type: Journal Article
• Authors: Güçlü, Ç.Ş.; Özdemir, A.F.; Karabulut, A.; Kökce, A.; Altındal, Ş.
• Is Part Of: Materials science in semiconductor processing. Volume 89(2019)
• Page Start: 26
• Page End: 31
• Publication Date: 2019-01
• Subjects: Au/Ti)/Al2O3/n-GaAs SBDs -- Atomic layer deposition -- Negative capacitance in the forward bias C-V curves -- Temperature and voltage dependence; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2018.08.019
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: In this study, a metal-insulator-semiconductor (MIS) type Schottky barrier diodes (SBDs) were fabricated by growing a thin Al2 O3 insulator layer between Au/Ti and n -GaAs using atomic layer deposition (ALD) method. The effect of temperature and voltage on interface states ( N ss ) and series resistance ( R s ) of the (Au/Ti)/Al2 O3 / n -GaAs (MIS) type Schottky barrier diodes (SBDs) was investigated using the capacitance/conductance-voltage ( C/(G/ω)-V ) data measured in wide range of temperature (200–380 K) and voltage ( ± 5 V). It was found that C and G / ω are strongly dependent on temperature and voltage. The value of C in the forward bias region reaches to maximum and then becomes negative. This negative capacitance (NC) behavior of this SBD is observed for each temperature level. Also, capacitance-current (C-I) and conductance-current (G/ω-I) plots were drawn to explain the NC behavior. The negative value of C in the accumulation region corresponds to the maximum value of G/ω. Such behavior of C can be explained by the loss of interface charges located at (Al2 O3 )/n-GaAs interface because of impact ionization process, the existence of surface states (Nss ), series resistance (Rs ) and interfacial of (Al2 O3 ) oxide layer.Therefore, the voltage dependent profiles of Rs and Nss were obtained using Nicollian-Brews and Hill-Colleman methods for enough high forward biases as a function of temperature at various positive bias voltages. The changes in Rs and Nss values were attributed to restructure and reordering of the carriers under temperature and voltage effects.