Gallium nitride (GaN) is a promising material for next-generation high-power applications due to its wide bandgap, high breakdown field, high electron mobility, and good thermal conductivity. From a structure point of view, the vertical device is more suitable to high-power applications than planar ...
Gallium nitride (GaN) is a promising material for next-generation high-power applications due to its wide bandgap, high breakdown field, high electron mobility, and good thermal conductivity. From a structure point of view, the vertical device is more suitable to high-power applications than planar devices because of its area effectiveness. However, it is challenging to obtain a completely upright vertical structure due to inevitable sidewall slope in anisotropic etching of GaN. In this letter, we design and analyze the enhancement-mode n-channel vertical GaN MOSFET with variation of sidewall gate angle by two-dimensional (2D) technology computer-aided design (TCAD) simulations. As the sidewall slope gets closer to right angle, the device performances are improved since a gradual slope provides a leakage current path through the bulk region.
Gallium nitride (GaN) is a promising material for next-generation high-power applications due to its wide bandgap, high breakdown field, high electron mobility, and good thermal conductivity. From a structure point of view, the vertical device is more suitable to high-power applications than planar devices because of its area effectiveness. However, it is challenging to obtain a completely upright vertical structure due to inevitable sidewall slope in anisotropic etching of GaN. In this letter, we design and analyze the enhancement-mode n-channel vertical GaN MOSFET with variation of sidewall gate angle by two-dimensional (2D) technology computer-aided design (TCAD) simulations. As the sidewall slope gets closer to right angle, the device performances are improved since a gradual slope provides a leakage current path through the bulk region.
In this work, we investigated the effects of sidewall angles on electrical characteristics of enhancement-mode n-channel vertical GaN MOSFET in terms of Imax, Ron, Vth, S, and VB. As the result, larger sidewall angle improves the overall device performances.
대상 데이터
1(a)-(b) present the three-dimensional schematic view and the cross-sectional view of the simulated GaN MOSFET with an indication of the current path. The high-κ gate oxide material is Al2O3 and its equivalent oxide thickness (EOT) is 30 nm. The gate workfunction is 5.
성능/효과
In this work, we investigated the effects of sidewall angles on electrical characteristics of enhancement-mode n-channel vertical GaN MOSFET in terms of Imax, Ron, Vth, S, and VB. As the result, larger sidewall angle improves the overall device performances. Therefore, it would be critical to construct the sidewall gates with right angles as much as the anisotropic dry etching permits, for both device performances and area-effectiveness.
Therefore, it would be critical to construct the sidewall gates with right angles as much as the anisotropic dry etching permits, for both device performances and area-effectiveness. One drawback that sharp slope might bring is the breakdown characteristics but it would overcome by appropriate passivation techniques relieving the electric field at the gate edge.
As the result, larger sidewall angle improves the overall device performances. Therefore, it would be critical to construct the sidewall gates with right angles as much as the anisotropic dry etching permits, for both device performances and area-effectiveness. One drawback that sharp slope might bring is the breakdown characteristics but it would overcome by appropriate passivation techniques relieving the electric field at the gate edge.
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