Electrical Properties of Metal–Insulator–Semiconductor Capacitors on Freestanding GaN Substrate

Abstract

The electrical properties of GaN metal–insulator–semiconductor (MIS) capacitors with as-grown SiO2, annealed SiO2, and SiN x insulators were investigated by capacitance–voltage (C–V), current–voltage (I–V), and time-dependent dielectric breakdown (TDDB) measurements. The MIS capacitor with the SiN x insulator was determined to have a lower interface trap density of 1×1011 cm-2 eV-1 than the MIS capacitors with the as-grown and annealed SiO2 insulators. In addition, the dielectric lifetime of the SiN x insulator was extrapolated to be more than 20 years at an even high voltage at room temperature. These results indicate that the high insulator/GaN interface quality and high reliability required for high-performance power devices can be achieved by the deposition of the SiN x insulator on GaN.

Hydrogen Sensors Using Nitride-Based Semiconductor Diodes: The Role of Metal/Semiconductor Interfaces

“…Since the plot of log ( J / E 2 ) versus 1/ E is linear, as shown in Figure 7(a), the oxide conduction is FN conduction. The barrier height extracted from the FN plot as shown in Figure 7(a) is 2.9 eV, and this value is found to be consistent with the previously reported values for the SiO 2 /GaN interface [28,29]. …”

“…Figure 7(c) shows a linear relation, suggesting that the dielectric conduction is Pool–Frenkel emission. The Si x N y dielectric is well known for showing Pool–Frenkel emission [28,31,32], consistent with the result shown in Figure 7(c). The Pool–Frenkel emission is due to emission of trapped electrons into the conduction band.…”

“…Here, the value of the effective mass used was equal to m dielec = 0.5 m [28]. Since the plot of log ( J / E 2 ) versus 1/ E is linear, as shown in Figure 7(a), the oxide conduction is FN conduction.…”

Hydrogen-induced change in the electrical properties of metal-insulator-semiconductor Pt–GaN diodes

“…2͑a͒, the oxide conduction is FN conduction. 16,17 On the other hand, for MIS Pt-GaN diodes with a SiO 2 dielectric, the measured I-V data in a H 2 ambient were fitted using the Pool-Frenkel emission model, as shown in Fig. 2͑a͒ is 2.9 eV, and this value is found to be consistent with the previously reported values for the SiO 2 / GaN interface.…”

Control of Ga-oxide interlayer growth and Ga diffusion in SiO2/GaN stacks for high-quality GaN-based metal–oxide–semiconductor devices with improved gate dielectric reliability

“…Judging from the energy bandgap and conduction band offset between the insulators and the GaN-related materials, alumina (Al 2 O 3 ), SiO 2 , and their nitrides seem to be possible candidates for gate dielectrics. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Since the atomic layer deposition (ALD) technique for producing high-quality Al 2 O 3 was established, ALD-Al 2 O 3 films have been widely used for GaN-based MOS devices. 4,6,7,[10][11][12] However, regardless of the film deposition technique used, Al 2 O 3 involves an essential problem of electron trapping, 6,13,14) thus leading to significant I d -V g hysteresis and V th instability (positive V th shift).…”