MC simulation of ultrafast transistor using ballistic electron in intrinsic semiconductor and its fabrication feasibility

High Open-Circuit Voltage Gain in Vertical InGaAs Channel Metal–Insulator–Semiconductor Field-Effect Transistor Using Heavily Doped Drain Region and Narrow Channel Mesa

“…[1][2][3][4][5][6][7] To surpass these physical limits, we have proposed a vertical InGaAs channel metal-insulator-semiconductor field-effect transistor (MISFET) with an InP/InGaAs heterostructure launcher and an undoped channel. [8][9][10][11][12][13][14][15][16][17][18][19][20] Hot electrons propagate in the undoped channel in the vertical MISFET, and high-speed operation with a high current density is expected. 11,21) We had previously fabricated such a device with a 15-nmwide channel mesa, and observed a 7 MA/cm 2 drain current density.…”

“…[8][9][10][11][12][13][14][15][16][17][18][19][20] Hot electrons propagate in the undoped channel in the vertical MISFET, and high-speed operation with a high current density is expected. 11,21) We had previously fabricated such a device with a 15-nmwide channel mesa, and observed a 7 MA/cm 2 drain current density. 18) However, the open-circuit voltage gain (ratio of transconductance g m to output conductance g o ) was only 0.3, as shown in Fig.…”

InP/InGaAs Hot Electron Transistors with Insulated Gate

“…Thus, elimination of the doped layer from the propagation region in hot electron transistors provides the possibility of high-speed operation. [1][2][3][4] By a Monte Carlo simulation, the estimated speed of hot electrons was over 7 Â 10 7 cm/s and the estimated cutoff frequency was over 1 THz when the current density was over 700 kA/cm 2 . 4) In previous study, 1,2) we fabricated hot electron transistors without a doped layer in the propagation region by fabricating a 25-nm-wide emitter and Schottky gate electrodes located at both sides of an emitter mesa.…”

“…[1][2][3][4] By a Monte Carlo simulation, the estimated speed of hot electrons was over 7 Â 10 7 cm/s and the estimated cutoff frequency was over 1 THz when the current density was over 700 kA/cm 2 . 4) In previous study, 1,2) we fabricated hot electron transistors without a doped layer in the propagation region by fabricating a 25-nm-wide emitter and Schottky gate electrodes located at both sides of an emitter mesa. Hot electrons were generated using a resonant tunneling barrier structure as an electronic launcher.…”

“…9) Thus we cannot confirm the transit electrons are ballistic although dimension of transit layer and potential height of heterolauncher are sufficient for true ballistic transportation in Monte Carlo simulation. 4) Because a part of collector current cannot be controlled by gate bias described as the leak current, the part of the current was flown through unexpected current path. To confirm gate-controlled current is ballistic, measurement of speed of electron, e.g., transient response in microwave measurement will be required.…”