Research Paper A predictive model for wafer probe burn phenomenon Baha Zafer a, *, Bahadır Tunaboylu b a Department of Mechanical Engineering, Istanbul University, Universite Mahallesi Avcılar, Istanbul 34254, Turkey b Department of Industrial Engineering, Istanbul Sehir University, Kustepe Caddesi Uskudar Istanbul, 34662, Turkey H I G H L I G H T S • Probe burn phenomenon is investigated with experimental and numerical methods. • The relation between mechanical degradation and temperature distribution of the probe is shown and examined. • Results suggest that both experimental and numerical approaches are comparable and complementary. ARTICLE INFO Article history: Received 6 June 2015 Accepted 21 December 2015 Available online 31 December 2015 Keywords: Wafer probe Probe burn Numerical simulation Joule heating Vertical spring probe A B ST R AC T Coupled thermal-electric computational mechanics techniques have been developed to understand the temperature distribution along a special design spring and cantilever probe body in order to model the probe burn phenomenon for conduction. The experimental maximum current carrying capability tests have been performed and compared with numerical solutions. Reasonably good agreement was ob- served between experimental and numerical results. A predictive model was developed as a design tool to enable faster probe design for cantilever or vertical types, assembly and test cycle for a wafer sort en- vironment. In addition to the first mode, transient heat transfer between a heated spring probe and its close environment is investigated. A continuum finite volume simulation is used to analyze the heat flow within and from the resistively heated probe to its environment. Experimental results are conducted for spring probe with laminar air flow and without air flow. The numerical and experimental results are com- pared and high similarity is observed. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Recent advances in semiconductor process technologies have enabled the design of complete electronic systems on a single chip. In order to handle the complexity and also to satisfy the increas- ing demand of the market for quicker supply, design engineers typically use computational mechanics techniques in their designs especially for structural analysis and thermal management [1]. Wafer level test is the first step in the manufacturing test process, where the chip in bare wafer form is tested by using the input/output (I/O) terminals of the chip for manufacturing defects. The devices are subjected to standardized parametric and functional tests such as electrical excitations and thermal cycles [2]. In the wafer level test, an individual chip is tested using probe needles of a probe card contacting to pads on a die. The wafer contact is becoming an important issue because of the difficulty in controlling the applied probe force on a contact pad and power delivery to the chip through the probe from the tester gen- erating conductive thermal effects due to Joule heating. Probe burn during wafer test is becoming increasingly costly in wafer manu- facturing since probe replacement is very difficult or, in some cases not possible for newer probe card technologies. It can be disrup- tive for the test floor flow since the probe card needs to be sent for repair or retired depending on the type of the technology or con- dition of the card after probe burn failures. In this paper, the 3D transient thermal conduction equation with Joule heating is used as a source term to compute temperature dis- tribution on the cantilever probe body. In addition, heat convection between the heated spring probe body and its environment is com- puted. A computational model for the cantilever wafer probes and special design vertical/spring probes for predicting the tempera- ture rise along a probe body and heat loss in the case of convection under laminar flow situation is developed to investigate the probe burn effects and compare them with the experimental results. In the experiments, the relation between the maximum current car- rying capability (CCC) and the mechanical degradation of a probe is monitored. In addition, the effects of critical geometrical factors of the probing needle including probe (base) diameter and tip di- ameter on the temperature distribution are evaluated. A parametric study of the effect of these probe design parameters on the Abbreviations: Iapp., applied current; BCF, balanced contact force; CCC, current carrying capability; Imax, the critical steady state current value; UDF, user defined function. * Corresponding author. Tel.: +905554661298; fax: 0212 234 7634. E-mail address: baha.zafer@istanbul.edu.tr (B. Zafer). http://dx.doi.org/10.1016/j.applthermaleng.2015.12.083 1359-4311/© 2015 Elsevier Ltd. All rights reserved. Applied Thermal Engineering 98 (2016) 610–616 Contents lists available at ScienceDirect Applied Thermal Engineering journal homepage: www.elsevier.com/locate/apthermeng