Capacitance monitoring while flex testing

Abstract

As most other modes of failure have been dramatically reduced over the years, cracking due to stresses from boards bending have gained prominence.

Finite‐Element Analysis of Ceramic Multilayer Capacitors: Failure Probability Caused by Wave Soldering and Bending Loads

“…The simulation correlates with the obtained fracture patterns of the measurements for Mode I failure. The crack paths compare very well with the crack paths determined by Prymak and Bergenthal, 5 which were obtained using a three-point flex test.…”

“…3,4 Mechanical loading occurs during component integration or circuit operation in the form of board bending. 5 Cracks that change the mechanical and, especially, the electrical performance of MLCs may result from this loading. Three different component sizes (1206, 1210, and 1812; the first two digits of these four-digit size numbers indicate the component length, the last two digits is the component width, given in increments of 0.01 in.)…”

Failure Prediction of Multilayer Ceramic Capacitors (MLCCs) under Temperature-Humidity-Bias Testing Conditions Using Non-Linear Modeling

“…그러나, 유전체의 두 께가 얇아지고 이를 지나는 전하량은 증가하면서 MLCC 의 고장률도 높아지게 되었고 MLCC와 보드를 기계적 전 기적으로 결합하는 인터커넥트의 불량과 결합하여 제품 고장의 일으키는 원인이 되기도 한다. [2][3][4][5] MLCC의 건전성은 절연저항, 정전용량, 손실 계수 (dissipation factor) 등의 전기적 파라메터를 통해 비파괴 적으로 측정할 수 있다. 6…”

A Comprehensive Surface Mount Technology Solution for Integrated Circuits onto Flexible Screen Printed Electrical Interconnects

“…While the surface mount technology (SMT) clearly depends on the materials of the assembly, requirements on the end product remain the same, for instance mechanical bendability, thermal reliability and electrical functionality. So far, flip chip-on-flex systems have been realized by adopting flexible electrically conductive adhesives ( [7], [8]), smaller chip sizes [10], thinned ICs ( [9], [11]) or by a combination of the above [12]. Embedding the assembled system into a sandwich structure enhances reliability of the chip-on-flex system, for instance by lamination or spin coating of a protective polymeric cladding onto a thinned IC [14].…”