Ag/n–Si/p–MgSe/(Ag, C, Au, Pt) devices designed as current rectifiers, photodetectors and as ac signal filters suitable for VLC, IR and 6G technologies

Abstract

Herein the fabrication and practical applications of p-MgSe thin films as active p-layer of electronic devices are reported. MgSe films are prepared by a vacuum evaporation technique onto n-Si substrates under a vacuum pressure of 10-5 mbar. The films are morphologically, structurally, electrically and opto-electronically investigated. Having identified the work function of p-MgSe as 6.74 eV, the role of Ag, C, Au and Pt metal contacts on the performance of the n-Si/p-MgSe (SM) diodes are studied. It is observed that high rectification ratios of ~104 and 102 are achieved at an applied voltage of 3.0 V for the Ag/SM/C and Ag/SM/Ag diode structures, respectively. In addition, a current responsivity to visible and infrared light of ~0.70 A/W is observed for the Ag/SM/Ag channels. The noise equivalent ratios, the external quantum efficiency and the detectivity of the Ag/SM/Ag diodes suit requirements of visible light and infrared communication detectors. Moreover, studies of the capacitance-voltage characteristics showed capacitor characteristics. The depleting of the Ag/SM/Ag capacitors is possible up to 50 MHz. Furthermore, analyzing the capacitance, resistance and cutoff frequency spectra have shown that the Ag/SM/Ag device channels can perform as negative resistance sources with cutoff frequency values that suits 6G technology requirements

Formation and Characterization of MgSe Alloys by Pulsed Laser Welding Technique

“…To understand whether the resulting structure of the pressed pellets is related to MgSe crystals or not, diffraction angles of patterns of cubic MgSe crystals are given on the right side of Table 2. [5,6] The observed diffraction patterns are centered at diffraction angles (2𝜃) different from those of MgSe compound, Mg, and Se. We attempted to explore the observed crystal structure using the "TREOR 92" software packages.…”

“…On the other hand, the structural parameters are calculated by benefiting from the maximum peak width at full wave half maximum to estimate the peak boarding (𝛽). Namely, the crystallite sizes (D = 0.94𝜆 𝛽 cos𝜃 [6,7] ) and the strain (𝜀 = 𝛽 4 tan 𝜃 [6,7] ) in the studied samples were calculated and listed in Table 1. It is clear from the table that the largest crystallite size and least strain are obtained for PLW-5 and PLW-50-1 samples; however, because PLW-50-1 samples are composed of 81.52 at% Mg we shall consider the PLW-5 samples as ideal and optimal samples having a stoichiometric composition, large crystallite sizes, and least strains.…”

“…Examples of these materials are Mg x Cd 1-x Se alloys [4] and MgSe thin films. [5,6] The aforementioned materials have been found to be suitable for the fabrication of multifunctional devices, such as broadband photodetectors, microwave resonators, and current amplifiers. [5,6] In light of the works mentioned above, we were motivated to try producing MgSe alloys by laser welding.…”

“…[5,6] The aforementioned materials have been found to be suitable for the fabrication of multifunctional devices, such as broadband photodetectors, microwave resonators, and current amplifiers. [5,6] In light of the works mentioned above, we were motivated to try producing MgSe alloys by laser welding. This ultrafast technique produces alloys, compounds, and composites within a few minutes.…”

Growth and Characterization of Lanthanum Germanide Thin Films by the Thermal Evaporation Technique

“…These values are crucial for thin film devices used in terahertz data transmission, as they align with the requirements of 6G technology, operating in the spectral range of 100 GHz to 30 THz. [22,41,42] In order to obtain detailed information about the optical conductivity parameters of the La 6 Ge films as terahertz filters the imaginary part is modeled using Drude-Lorentz approaches for optical conduction. The model is summarized by the equations [26] 𝜀…”