Effect of GaN buffer polarization on electron distribution of AlGaN/GaN heterostructure

•The formation of 2DEG in AlGaN/GaN heterostructure is discussed in detail.•Self-consistent Schrodinger–Poisson numerical simulation is used to modulate the AlGaN/GaN/substrate structure.•It is predicted by that large amounts of electrons will accumulate at the GaN/substrate interface.

The formation of 2DEG in AlGaN/GaN heterostructure is discussed in detail. A misunderstanding about the 2DEG sheet density expression is clarified. It is predicted by theoretical analysis and validated by self-consistent Schrodinger–Poisson numerical simulation that under the force of GaN polarization, large amounts of electrons will accumulate at the GaN/substrate interface in AlGaN/GaN/substrate HEMT structure.