Equivalent circuit model of UTC photodiode

Characterization of high‐photocurrent and high‐speed INP‐based uni‐traveling‐carrier photodiodes at 1.55‐μm wavelength

“…In order to overcome these difficulties, a semi‐analytical method, which combines the advantages of using analytical method and numerical optimization method, for extracting the model parameters of UTC‐PD is proposed in this paper. Comparing with previous literatures , current method has the following advantages: The equivalent circuit model is developed basing on actual device structure and physics. The dipole‐doped structure at the InGaAs/InP heterostructure interface has been taken into account in the equivalent circuit model to simulate its effectiveness on suppressing the current blocking effect . Most of the circuit component parameters, including parasitic and intrinsic parameters, can be extracted directly from a set of closed‐form expressions based on the measured reflection coefficients ( S 22 ) and frequency responses ( S 21 ) of devices. Only one parameter (capacitance of the dipole‐doped structure C dd ) cannot be extracted directly by using analytical method.…”

High-speed and high-photocurrent InP-based uni-traveling-carrier photodiode

“…As can be seen from the Smith Chart in Figure 5 Bias = -5 V In summary, the semi-analytical method introduced above, which combines the advantages of using analytical method and numerical optimization method, for extracting the small-signal model parameters of UTC-PD is proposed in this thesis has the following advantages compared to previous literatures [25][26][27][28][29][30][31][32] :…”

“…Modeling of photodiodes is very important for a careful analysis of their performance and design issues. For high-output and high-speed photodiodes, various modeling methods, such as physics-driven modeling, analytical modeling, empirical modeling and equivalent circuit modeling, have been investigated (especially for PIN-PDs) [25][26][27][28][29][30][31][32]. Wang et al [25,26] and Wu et al [27] both proposed their analytical equivalent circuit models for high-performance photodiodes.…”

“…The accuracy of the results depends greatly on the parameters of the equivalent circuit model; thus a good equivalent circuit model is not merely helpful for prediction of the performances of devices but also important for extracting model parameters conveniently and accurately [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. Numerical optimization techniques are usually used to determine the optimal values of model parameters [35,38].…”

“…However, the accuracy of the optimization methods can vary largely up to the optimization method used and the initial values of model parameters selected [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]. Nonphysical and nonunique results of the extracted parameter could be generated.…”