Electrically pumped random laser device based on Pd/SiO2/ZnO nanorods MIS structure

• Electrically pumped random laser at room temperature with Palladium metal contact. • High crystal quality of ZnO nanorods synthesized via chemical bath deposition. • Formation of Schottky junction in Pd/SiO 2 /ZnO nanorods structure. • Relatively low threshold current (37.5 mA). • Random lasing explained by electron-hole pair radiative recombination. Electrically pumped random lasing based on Pd/SiO 2 /ZnO nanorods (NRs) structures is demonstrated. Chemical bath deposition (CBD) technique was used to synthesize the ZnO NRs. Then, an insulating layer of SiO 2 was deposited via radio frequency (RF) magnetron sputtering. After that, direct current (DC) magnetron sputtering was used to deposit palladium (Pd) metal contacts on the sample through a shadow mask. The electrical, morphological as well as optical characteristics of the ZnO NRs were analyzed. The device exhibits typical Schottky diode current–voltage ( I-V ) characteristics at a turn-on voltage of 6.18 V. The electroluminescence (EL) spectra shows good random lasing behavior with lasing peaks centered at approximately 380 nm and exhibited a threshold current of 37.5 mA. This report reveals Pd as a relatively cheaper material and low-cost CBD fabrication method is sufficient to fabricate electrically pumped random laser devices. Furthermore, this report also present a new way to interpret the mechanism of random lasing in the device.