ZnPc based multifunctional devices designed as fast capacitors, rectifiers, infrared detectors and microwave resonators adequate for 6 G technology applications

Abstract

Herein Zinc phthalocyanine (ZnPc) based multifunctional devices are fabricated and characterized. The device fabrication included formation of an Au nanosheets onto n-Si wafers and coating these nanosheets with 500 nm thick ZnPc layer. Silver and platinum were used to form a Schottky and an ohmic contacts with n-Si and ZnPc, respectively. The device hybrid structure (Ag/n-Si/Au/p-ZnPc/Pt; abbreviated as ASZ) is composed of Ag/n-Si Schottky arm and p- and n- layers forming pn junction separated by Au nanosheets. Electrical and photoelectrical measurements on the ASZ devices have shown their ability to perform as conventional metal-oxide-semiconductor capacitors (CMOS). These CMOS devices showed light and frequency controlled charge accumulation, depletion and inversion mechanisms within the range of 1.0-50 MHz. The flat band and threshold voltages of the ASZ capacitors are engineered by the imposed ac signal frequency and by infrared (IR) light. In addition, ASZ devices performed as biasing controlled IR photosensors and as current rectifiers. A rectification ratio of 103, IR light sensitivity of 39, specific detectivity of .96×109 Jones and current responsivity exceeding 9.0 mA/W are recorded at biasing voltage of 4.5 V. Moreover ASZ devices displayed microwave resonator characteristics presented by negative capacitance effect, resonance –antiresonance phenomena and high microwave cutoff frequency. The latter is larger than 10 GHz nominating the device for 6G technology applications.