Investigation of dimensional and heat source effects in Lock-In Thermography applications in semiconductor packages

3D Defect Localization on Exothermic Faults within Multi-Layered Structures Using Lock-In Thermography: An Experimental and Numerical Approach

“…Similar to what we found in the results of the three-layer SSHSC (thin), the estimated depth at the lower lock-in frequency has a relatively larger error compared to that at the higher lock-in frequency. This trend coincided well with the results of Kijkanjanapaiboon et al [ 19 ], who determined that, when a specimen becomes thinner at a lower lock-in frequency, the difference in its phase shifts becomes significant.…”

“…Since the seminal work on LIT by Busse et al [ 10 ], many research efforts have been devoted to the application of LIT to ICs, semiconductor packages, or semiconductor devices for FA [ 2 , 3 , 12 , 16 , 17 , 18 , 19 ]. Breitenstein et al [ 12 ] investigated the shunting and leakage phenomena in electronic devices such as solar cells and metal oxide semiconductor (MOS) structures by developing dynamic precision contact thermography (DPCT), which is the first LIT technique enabling the detection of temperature of 100 μK with a spatial resolution of 30 μm.…”

“…Considering these facts, the phase shift for 3D defect localization on the effects of the thermal contact resistance between two different layers should be quantified by various heat source configurations [ 18 ]. Kijkanjanapaiboon et al [ 19 ] investigated the accuracy of the interpretation of the LIT data based on semi-infinite models, which have a heat source located at the origin and homogeneous material with infinite dimensionality, by using an analytical solution and finite element (FE) analysis. They focused on analyzing the effects of using finite dimensionality, heat source configuration, the convective heat transfer coefficient, the thickness and thermal diffusivity of the material, and the lock-in frequency in a homogeneous and single material, by calculating the difference in the phase shift and the estimated depth of the error.…”

“…Furthermore, their examination was based on a semi-infinite model only. Actually, to locate the depth using LIT, it is of considerable importance to understand the effect on the 3D defect localization by the system parameters and sample properties such as the sensitivity of the infrared camera, the optical properties of material such as transparency and emissivity, the thermal properties of the material such as thermal diffusivity, the sampling rate, and heat source configuration [ 19 , 20 ]. Therefore, the combination of experimental and numerical demonstrations for actual LIT applications is very important for the success of 3D defect localization in 3D IC or semiconductor packages.…”

Implementation of Fully Coupled Electromigration Theory in COMSOL

“…The GCM has been implemented in ANSYS published in refer. [24][25][26][27][28]. In the GCM model, the diffusion equation (mass conservation equation) is not a standard form of the diffusion equation in the built-in multiphysics theory in ANSYS.…”