Investigation on the Electrical Characteristics of PN-Type Porous Silicon with Gate Electrode

• Main Authors: CIAN-DE JIANG, 姜謙德
• Other Authors: Yen Hsu-Nan
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/16157257612462745344

碩士 === 聖約翰科技大學 === 電子工程系碩士班 === 101 === This study pastes blue tapes on the P-side surface of nine inspected specimens as protection films. These inspected specimens are first carved out three patterns of large circle, medium circle and small circle, respectively, by a CO2 laser carving machine. Each circle pattern has three experimental specimens. After tearing Blue-Tape, these specimens are put into etching grooves to proceed anodic electrochemical etching of porous silicon with different experimental parameters. We observed and recorded the optical excitation light colors these porous silicon under 365nm wavelength UV light projection. Then emission spectra and relative intensity of these porous silicon specimens were recorded by using a photoluminescence (PL) spectrum analyzer. Tiny structures of porous silicon surface and roughness were observed by applying the 3D surface profiler, field emission scanning electron microscope and scanning electron microscopy. Finally, the self-made gate electrodes of different shapes were put on the porous silicon specimens, and separately measured by IV-CV measurement instrument under four light projection situations, i.e., the darkness, daylight, UV light and halogen lighting. Experimental results show that the porous silicon specimens of large, medium and small circle patterns are slightly different even under the same formation parameters. This means that the etching area will affect the formation of porous silicon, so that affect the final optical sensing properties. Based on the experimental results, the medium circular pattern, etching solution (HF: Alchol = 1:4), etching time of 5 minutes or 10 minutes and constant current 0.01A are the parameter combinations so that the resistance has the greatest change in this paper.