tailieunhanh - Data processing methods for deep level transients measurement

This paper provides almost complete review on DLTS, focusing on the main three approaches widely used today. We also summarize the development of this method in the Faculty of Physics, VNU University of Science. | VNU Journal of Science: Mathematics – Physics, Vol. 34, No. 4 (2018) 44-61 Data Processing Methods for Deep Level Transients Measurement Pham Quoc Trieu, Hoang Nam Nhat* Faculty of Physics, VNU University of Science, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam Received 17 December 2018 Revised 20 December 2018; Accepted 22 December 2018 Abstract: The year 2019 marks 45 years in the development of Deep Level Transient Spectroscopy (DLTS) - the signal processing method for determination of overlapping deep levels in semiconductors. From its introduction in 1974 by David Lang (. Lang, J. Appl. Phys. 45, 1974, ) to this date the DLTS method has undergone many changes and modifications: some were purely theoretical speculations, some were to also include new experimental arrangement and technique. This paper provides almost complete review on DLTS, focusing on the main three approaches widely used today. We also summarize the development of this method in the Faculty of Physics, VNU University of Science. Keywords: 1. Introduction The existence of the deep levels transient is important phenomenon in semiconductor physics. The characterization of the deep traps faced many difficulties until 1974 when Lang has introduced a spectroscopic method called the Deep Level Transient Spectroscopy (DLTS) [1]. This method allows to detect with appropriate accuracy the existence of overlapping transients cast in the form of the capacitance dependence on time C (t ) Ce ent (). The basic physical parameters of the traps such as the activation energy, capture cross-section and concentration can be determined by this technique. The Lang's method has been widely utilized today as a standard tool, although it is known to have several limitations, such as a slow run and low resolution. To extract the trap parameters from the exponential decays, Lang has introduced a signal form of S(T)=C(t1) C(t2) which is technically realized using a double boxcar circuit, which .