Computer (IBM PC) based I-V, C-V system

摘要

An automated C-V, I-V system has been developed. The various modules of the system are current meter, capacitance meter, data acquisition system, voltage source and personal computer (PC). Data acquisition system is constructed using a 12-bit A/D converter and the voltage source using two 12-bit fast D/A converters. These modules the interfaced to the computer. User friendly software has been developed in TURBO BASIC in an interactive mode. Form opening menu the user can select the different modes of the software like I-V measurement, C-V measurement, I-V analysis and C-V analyses. I-V analyses provides the values of ideality factor, n, saturation current I{sub}s barrier height Φ{sub}(Bn) and effective lifetime of the charge carriers, τ{sub}O C-V analysis gives the information on carrier concentration, N{sub}D, nature of the junction (linear/abrupt), barrier Φ{sub}(Bn) built-in potential, V{sub}(bi), Plots of I/C{sup}2 V{sub}S V{sub}R or I/C{sup}3 V{sub}S V{sub}R and depth profile of the carriers. Further, the same software can be used to analyse the data taken manually. The paper describes the hardware and software details of computer controlled (automated) I-V and C-V measurement system.