Current gain enhancement effect by gate doping in bipolar-mode field-effect transistor

New Schottky-Gate Bipolar-Mode Field-Effect Transistor (SBMFET): Design and Analysis Using Two-Dimensional Simulation

“…1. The device parameters (P + -gate junction depth, epilayer thickness and its doping, channel width, source, drain and P + gate peak doping) are chosen based on reported results in literature [12][13][14][15] and are tabulated in Table I the Schottky gate to inject excess holes into the N-drift region [32]. When the drain voltage is increased to V DS = 5 V at I G = 0.4 μA/μm, the holes are pushed deeper towards the source making the low resistance conductivity modulated region shorter as shown in Fig.…”

“…1. The device parameters (P + -gate junction depth, epilayer thickness and its doping, channel width, source, drain and P + gate peak doping) are chosen based on reported results in literature [12][13][14][15] and are tabulated in Table I. Two-dimensional numerical simulations were performed In order to understand the physics of the device, particularly the effect of Schottky interface, energy band diagrams of the Metal gate-N epilayer junction simulated using MEDICI are shown in Fig.…”

“…7 in which we can see that the SBMFET exhibits a higher current gain compared to the conventional BMFET. It has been shown that for a given gate current, as the gate doping increases, the epilayer gets filled by a higher carrier density, which decreases the ON-resistance, and results in an increased drain current [15]. The doping concentration in the P + gate is always less than the free carrier concentration in the Schottky metal gate.…”

“…However, devices such as insulated gate bipolar transistor (IGBT) and bipolar mode field effect transistor (BMFET) use drift region conductivity modulation to derive very small ON resistance and hence negligible conduction losses [1][2][3][4]. BMFETs are also used very commonly in optical applications as an optically controlled switch [5][6][7][8] and have been reported both on GaAs [9][10][11] and silicon [12][13][14][15][16][17][18][19][20][21][22]. The most commonly studied BMFET devices have N-type epitaxial drift region and P + -gates.…”