Peck Model Research Articles

Influence of shear strength on long term biased humidity reliability of Cu ball bonds

This paper compares and discusses the influence of shear strength (in terms of shear-per mils-square) of Au and Cu ball bonds on the biased humidity reliability performance in SOIC 8LD leaded package. Biased (HAST) highly accelerated temperature and humidity stress test, 130 °C, 85 % RH) has been carried out to estimate the long term reliability of Au and Cu ball bonds. Lognormal reliability plots have been plotted for the three legs (control, leg 1 and leg 2) whereby Shear-per-mil-square of 6.68 is identified to have better mean-time-to-failure (t50) compared to other two legs. Open failure from biased HAST 96, 192 h are subjected for secondary electron microscopy cross-sectioning and found typical interfacial CuAl intermetallic compound corrosion microcracking. HAST failure rates have been analyzed and the Cu ball bond lifetime has been established by using Peck model. The obtained Cu ball bond lifetime, of SPMS of 6.68 is >25 years and belongs to wearout reliability data point. This proves significant influence of SPMS on biased HAST failure rate. The higher the ball bond shear strength the lower the failure rate of biased HAST test. Hence, we should implement control on the average SPMS of ≥7.50 g/mil2.

Time Evolution Degradation Physics in High Power White LEDs Under High Temperature-Humidity Conditions

A high temperature-humidity test is commonly employed to evaluate the humidity reliability of electronic devices. For an integrated circuit, the degradation mechanism under the high temperature-humidity test is metal corrosion, and Peck's model is used for extrapolating the test results at accelerated test conditions to the normal operating condition. Such extrapolation is possible as the underlying degradation physics is invariant from the accelerated test conditions to the normal operating condition for integrated circuits. However, this is not true for high power LEDs, as found in this paper. The degradation in the LEDs undergoes time evolution at either 95% or 85% relative humidity (RH) and 85 $^{\circ}\hbox{C}$ . We also found that the degradation physics are completely different among the various RH levels from 95% to 70%. The degradation process begins from bond pad contamination and Kirkendall void formation, galvanic dissolution, phosphor dissolution to encapsulant, and die attach delamination. Such time evolution degradation physics renders the inapplicability of the Peck model and presents a challenge in extrapolation of test results to the normal operating condition for lifetime prediction.

Rancang-Bangun Perangkat Silabus dan RPP Sains Kimia Bercirikan Model GI dengan Media Lingkungan untuk Siswa Kelas VII Sekolah Menengah Pertama

A set of syllabus and lesson plans of science chemistry charaterizing group investigation (GI) model andenvironment as learning resources for 7th-grade students of SMP has been developed. The development theproduct was intended to design an active and joyful instructional process for 7th-grade students of SMP inlearning science chemistry. The procedure of the development adopted Hannafin and Peck model that consists ofthree phases. This model was started with a need assessment and analysis (phase 1), then was designing process(phase 2), and finally development and implementation in a real teaching (phase 3). According to experts thedeveloped products are characterized by GI with environmental media. The result of research showed that theproducts could improve student’s activities in learning process.

Lifetime Estimation of a Photovoltaic Module Subjected to Corrosion Due to Damp Heat Testing

In this paper, a methodology is presented for estimating the lifetime of a photovoltaic (PV) module. Designers guarantee an acceptable level of power (80% of the initial power) up to 25 yr for solar panels without having sufficient feedback to validate this lifetime. Accelerated life testing (ALT) can be carried out in order to determine the lifetime of the equipment. Severe conditions are used to accelerate the ageing of components and the reliability is then deduced in normal conditions, which are considered to be stochastic rather than constant. Environmental conditions at normal operations are simulated using IEC 61725 standard and meteorological data. The mean lifetime of a crystalline-silicon photovoltaic module that meets the minimum power requirement is estimated. The main results show the influence of lifetime distribution and Peck model parameters on the estimation of the lifetime of a photovoltaic module.

열화데이터를 이용한 자색 연막수류탄(KM18)의 저장수명 평가

A violet smoke hand grenade(KM18) is used to generate signals. The grenade is considered to fail when its smoke emission time is longer than the specified one so that its smoke concentration becomes lighter. Accelerated degradation test for the grenade was performed, and then failure in smoke emission time was reproduced from the test. Stress for the degradation test was selected as temperature/humidity from the pre-test results. Degraded data of emission time from the accelerated test were analyzed through applying a distibution-based degradation model. Then, Peck Model was applied to predict the storage life under field conditions. In addition, the predicted storage life was compared with that of ASRP(Ammunition Stockpile Reliability Program).

Evaluation of AlGaInP LEDs reliability based on accelerated tests

High efficiency LEDs are replacing incandescent bulbs in many applications particularly those requiring durability and low power consumption. In some of these applications, as automotive and traffic signals, LEDs work in outdoor environment and in some cases in extreme temperature and humidity conditions. Main failure mechanisms have been identified for the different stress conditions (temperature/humidity accelerated tests). MTTF of 127,000 h have been evaluated for real working conditions by means of applying Arrhenius and Peck model values obtained in this paper.

Probabilistic physics-of-failure models for component reliabilities using Monte Carlo simulation and Weibull analysis: a parametric study

In reliability engineering, component failures are generally classified in one of three ways: (1) early life failures; (2) failures having random onset times; and (3) late life or ‘wear out’ failures. When the time-distribution of failures of a population of components is analysed in terms of a Weibull distribution, these failure types may be associated with shape parameters β having values <1, ∼1, and >1 respectively. Early life failures are frequently attributed to poor design (e.g. poor materials selection) or problems associated with manufacturing or assembly processes. We describe a methodology for the implementation of physics-of-failure models of component lifetimes in the presence of parameter and model uncertainties. This treats uncertain parameters as random variables described by some appropriate statistical distribution, which may be sampled using Monte Carlo methods. The number of simulations required depends upon the desired accuracy of the predicted lifetime. Provided that the number of sampled variables is relatively small, an accuracy of 1–2% can be obtained using typically 1000 simulations. The resulting collection of times-to-failure are then sorted into ascending order and fitted to a Weibull distribution to obtain a shape factor β and a characteristic life-time η. Examples are given of the results obtained using three different models: (1) the Eyring–Peck (EP) model for corrosion of printed circuit boards; (2) a power-law corrosion growth (PCG) model which represents the progressive deterioration of oil and gas pipelines; and (3) a random shock-loading model of mechanical failure. It is shown that for any specific model the values of the Weibull shape parameters obtained may be strongly dependent on the degree of uncertainty of the underlying input parameters. Both the EP and PCG models can yield a wide range of values of β, from β>1, characteristic of wear-out behaviour, to β<1, characteristic of early-life failure, depending on the degree of dispersion of the uncertain parameters. If there is no uncertainty, a single, sharp value of the component lifetime is predicted, corresponding to the limit β=∞. In contrast, the shock-loading model is inherently random, and its predictions correspond closely to those of a constant hazard rate model, characterized by a value of β close to 1 for all finite degrees of parameter uncertainty. The results are discussed in the context of traditional methods for reliability analysis and conventional views on the nature of early-life failures.

A Fundamental Overview of Accelerated Testing Analytical Models

This paper describes analytical models that are commonly used for product life estimation and accelerated life testing. Model descriptions include: Miner's "Rule" for describing accumulated fatigue damage; Coffin-Manson nonlinear power law, often applied to mechanical fatigue damage; Rudra model for CFF failures; Arrhenius steady-state temperature acceleration model for estimating chemical aging effects; Peck's model for accelerated combined temperature-humidity effects; and Kemeny model for combined temperature and voltage acceleration effects. The general form of these models will be presented along with specific guidance regarding: relative strengths and appropriate applications for each model; limitations and sources of uncertainty for each model; and example values for exponents and material coefficients.