Modulated Electric Field to Analyze Channel Coupling in InAlN/GaN Double-Channel HEMTs

To study the channel coupling effect of InAlN/GaN Double-Channel HEMTs (DC-HEMT) under different electric field strengths (E
f
), T-CAD simulations and actual device tests were performed. By analyzing the transfer characteristics, E
f
distribution, electron concentration (N
c
) distribution, and conduction band energy (E
c
) diagram under the same source-drain spacing (L
sd
) and different drain bias voltages (V
ds
), it is concluded that as the E
f
increases, upper and lower channel potential wells in the gate region gradually become deeper, but the potential well in the lower channel is deeper, making it easier for the upper channel electrons to leap to the lower channel and the coupling effect is enhanced.