A p-Si/n-GaN diode fabricated by nanomembrane lift-off and transfer-print technique

In this paper, we successfully demonstrated a high quality p-Si/n-GaN heterojunction diode through van der Waals bonding implemented by nanomembrane lift-off and transfer-print technique. A nanoscale native oxide layer is observed at the interface by transmission electron microscope, which plays a role as passivation-layer. The heterojunction diode has excellent electrical performance with a high rectification ratio of 4.75 × 10⁵ at $\pm 3$ V and a low reverse dark current density of 4.03 × 10^–4 A cm⁻² at −3 V. In addition, the heterojunction diode responds to both near ultraviolet (375.6 nm) and red light (650 nm) with responsivity of 429.9 mA W⁻¹ and 66.8 mA W⁻¹ (at −3 V) respectively. This result indicates that a large-lattice-mismatched semiconductor heterojunction can be fabricated based on GaN by using transfer-print technique, thereby expanding the operating band of GaN-based detectors from ultraviolet region to visible region. (paper)