Modulation of Semiconductor\nDoping of 2D GeSe in h‑BN/GeSe\nvan der Waals Heterostructure

Herein, a novel controllable and nondestructive semiconductor\ndoping\ntechnique is proposed by introducing defects in the h-BN/GeSe van\nder Waals heterostructure. A perfect n-/p-type channel layer can be\nachieved through charge transfer between the defective h-BN substrate\nlayer and the GeSe channel layer. The effect of this modulation doping\nstrategy on the carrier mobility of the channel layers is also investigated.\nIn the case of the h-BN/GeSe heterostructure with the introduction\nof boron vacancies, the electron mobility of 2D GeSe in the <i>x</i> (<i>y</i>) direction is 1479.11 (1343.95) cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup>, and the hole\nmobility in the <i>x</i> (<i>y</i>) direction\nis 1031.88 (864.44) cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup>. As for producing nitrogen vacancies in the h-BN/GeSe heterostructure,\nthe electron mobility of 2D GeSe in the <i>x</i> (<i>y</i>) direction is predicted to be as high as 1643.77 (1678.14)\ncm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup>, and the\nhole mobility in the <i>x</i> (<i>y</i>) direction\nis about 1129.51 (1563.50) cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup>, respectively. In contrast, the electron (hole) mobility\nin the <i>x</i>-direction is dramatically decreased to 705.29\n(630.85) cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup>, and the electron (hole) mobility in the <i>y</i>-direction\nis only 701.40 (481.37) cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup> for the GeSe layer by using the traditional semiconductor\ndoping method. The nondestructive doping strategy provides an effective\nmethod to modulate two-dimensional semiconductor channel materials\nwhile avoiding lattice damage, thus resulting in much higher carrier\nmobility. It indicates that the novel semiconductor doping technique\nhas a great promising application in electronic and optoelectronic\ndevices.