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Coronavirus, chip boom, and supply shortage: The new normal for global semiconductor manufacturing 冠状病毒、芯片热潮、供应短缺:全球半导体制造业新常态
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000026
Stephen M. Rothrock
Over the past 50 years, the semiconductor industry has faced its fair share of difficult challenges. The COVID-19 pandemic the world is currently experiencing has caused the worst downturn since the financial crisis of 2008, devastating global economies. And yet, the semiconductor industry has repeatedly shown incredible resilience in the face of adversity. Despite the pandemic, the market has not experienced such a dramatic upturn since 2003 and as a result, the new market upturn breaks open the fundamental flaws and risks of manufacturing concentration and outsourcing. At a time when the world is precariously dependent on Taiwan for semiconductors, how can the global supply chain forecast, manage, and plan for such sudden shifts in the future? Now more than ever before, advanced technology companies need to keep the finger on the pulse of supply and demand to successfully inform their strategic manufacturing decisions and remain agile to ensure continuity of supply. As chip demand booms in the midst of a supply shortage over the coming months and supply is no longer a given, what does the future hold for manufacturing fabs? Will greenfield become the rule rather than the exception in this new normal? How will the market upturn impact global fab location choices? Reflecting on some 20 years of experience completing international semiconductor manufacturing asset transactions in North America, Europe, and Asia, ATREG Founder, President, and CEO Stephen M. Rothrock will provide insights into the current global manufacturing asset market and how it is likely to evolve as part of the current market upturn.
在过去的50年里,半导体行业面临着相当多的困难挑战。当前全球正在经历的新冠肺炎疫情造成了2008年金融危机以来最严重的经济衰退,给全球经济带来了毁灭性打击。然而,面对逆境,半导体行业一再表现出令人难以置信的韧性。尽管疫情大流行,但市场自2003年以来从未出现过如此戏剧性的好转,因此,新的市场好转打破了制造业集中和外包的根本缺陷和风险。当世界对台湾半导体的依赖岌岌可危时,全球供应链如何预测、管理和计划未来这种突如其来的转变?现在,先进的技术公司比以往任何时候都更需要掌握供需脉搏,以成功地为其战略制造决策提供信息,并保持敏捷,以确保供应的连续性。在未来几个月供应短缺的情况下,随着芯片需求激增,供应不再是既定的,制造晶圆厂的未来将如何?在新常态下,绿地会成为常态而不是例外吗?市场好转将如何影响全球晶圆厂选址选择?ATREG创始人、总裁兼首席执行官Stephen M. Rothrock在北美、欧洲和亚洲完成了约20年的国际半导体制造资产交易,他将对当前的全球制造资产市场以及随着当前市场好转,它可能如何演变提供见解。
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引用次数: 0
Chiplets Heterogeneous Integration on High-Density Hybrid Substrate Using an Interconnect-Layer 利用互连层在高密度杂化基板上的小片异质集成
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000217
C. Peng, J. Lau, C. Ko, Paul Lee, E. Lin, Kai-Ming Yang, P. Lin, Tim Xia, Leo Chang, N. Liu, Curry Lin, T. Lee, Jason Wang, M. Ma, T. Tseng
In this study, a high-density organic hybrid substrate for chiplets heterogeneous integration is investigated. Emphasis is placed on the design, materials, process, fabrication, and characterization of the hybrid substrate with an interconnect-layer. A non-linear finite element analysis is performed to show the state of stress at the vias filled with a conductive paste of the interconnect-layer.
在本研究中,研究了一种高密度有机杂化衬底,用于芯片异质集成。重点放在设计、材料、工艺、制造和表征的混合衬底与互连层。非线性有限元分析显示了在填充导电浆料的互连层孔处的应力状态。
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引用次数: 0
Thermal and Reliability Performance Comparison of DBC-Based and Organic-Based Double-Sided Cooled Power Modules 基于dbc和基于有机双面冷却电源模块的热性能和可靠性比较
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000382
Tzu-Hsuan Cheng, Kenji Nishiguchi, Y. Fukawa, D. Hopkins
Direct Bonded Copper (DBC) is the most popular solution for conventional high-power modules because of superior thermal/electrical/mechanical performance and mature manufacturing. To meet the rising demand of power density and power rating, a Double-Sided Cooled (DSC) sandwich structure using dual insulated metal-clad substrates was proposed and DBC still dominated the substrate selection of DSC power modules. However, there are several long-existing reliability challenges of conventional DBC-based power modules and the cost of DBC is relatively high compared with organic and metal (e.g. lead frame) substrates. This study proposes a DSC 1.2 kV half-bridge power module using dual epoxy-resin Insulated Metal Substrate (eIMS) for solving DBC-based power module issues and providing a cost-effective solution. The thermal performance outperforms traditional Alumina (Al2O3) DBC-based DSC power module due to moderate thermal conductivity (10 W/mK) and thin (120 μm) epoxy-resin composite dielectric layer compared with Alumina. The breakdown voltage of this high thermally conductive organic dielectric is 5 kVAC (@ 120 μm) and the Glass Transition Temperature (Tg) is 300°C which is indispensable for Wide-Band-Gap (WBG) devices and high-power applications. In terms of thermal-mechanical reliability, the organic-based DSC power module can pass the thermal cycling test over 2000 cycles by optimizing the mechanical properties of the encapsulant material. In conclusion, this paper not only proposes a competitive organic-based power module but also a methodology of evaluation for thermal and mechanical performance.
直接键合铜(DBC)是传统大功率模块中最流行的解决方案,因为它具有优越的热/电/机械性能和成熟的制造工艺。为了满足不断增长的功率密度和额定功率的需求,提出了一种采用双绝缘金属包覆衬底的双面冷却(DSC)夹层结构,DBC仍然主导着DSC功率模块衬底的选择。然而,传统的基于DBC的功率模块存在几个长期存在的可靠性挑战,并且与有机和金属(例如引线框架)基板相比,DBC的成本相对较高。本研究提出了一种采用双环氧树脂绝缘金属基板(eIMS)的DSC 1.2 kV半桥功率模块,以解决基于dbc的功率模块问题,并提供了一种经济有效的解决方案。由于导热系数适中(10 W/mK)和较氧化铝薄(120 μm)的环氧树脂复合介电层,其热性能优于传统的氧化铝(Al2O3) DBC-based DSC功率模块。这种高导热有机介质的击穿电压为5 kVAC (@ 120 μm),玻璃化转变温度(Tg)为300°C,这对于宽带隙(WBG)器件和大功率应用是必不可少的。在热机械可靠性方面,通过优化封装材料的力学性能,有机基DSC电源模块可以通过2000次以上的热循环测试。综上所述,本文不仅提出了一种具有竞争力的有机电源模块,而且还提出了一种热性能和机械性能评估方法。
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引用次数: 0
High-Accuracy Pick-and-Place of Multiple Dies in Parallel Assisted by Capillary Self-Alignment 毛细管自对准辅助多模平行高精度取件
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000074
Birgit Brandstätter, B. Auer, H. Klingler, S. Scherbaum
Self-assembly of components driven by liquid surface tension is an attractive complement and even alternative to traditional high-accuracy pick-and-place as it offers high accuracy despite inaccurate robotic part placement. While capillary self-alignment through liquid solder is the standard technology for flip-chip processes, this work presents self-alignment of dies on wetted receptors on a temporary carrier: Low-viscosity liquid is jetted on each receptor where the liquid is contained through generation of hydrophilic and hydrophobic sections on the temporary carrier by plasma treatment. Deterministic die feeding by low-accuracy pick-and-place is conducted for single dies, as well as for batches of three dies and nine dies optimizing the equipment for best throughput to achieve both high accuracy and high productivity. The industry-ready and fully automated chip-to-wafer pick-and-place process is implemented into a fan-out wafer-level packaging production flow proving that self-alignment is capable of easing the stringent requirement for robotic alignment capability for pick-and-place systems in fan-out packaging for the single die-level step in this production chain. The self-alignment process is optimized, and failure modes such as poor liquid confinement, surface contamination, or excess force are identified and eliminated. Post-bond accuracy of <3 μm @ 3 σ at each point of the die is reached for dies of 3.1 mm x 3.1 mm in size. Using parallel die handling, high speeds of around 10 000 units per hour are made possible.
由液体表面张力驱动的组件自组装是传统高精度拾取和放置的一个有吸引力的补充,甚至是替代方案,因为它提供了高精度,尽管机器人零件放置不准确。虽然通过液体焊料的毛细管自对准是倒装芯片工艺的标准技术,但这项工作展示了在临时载体上的湿受体上的模具自对准:通过等离子体处理在临时载体上产生亲水性和疏水性部分,将低粘度液体喷射到每个受体上,其中包含液体。采用低精度取模方式对单个模具进行确定性送料,同时对批量的3个模具和9个模具进行优化,使设备达到最佳产量,实现高精度和高生产率。行业准备和全自动芯片到晶圆的拾取和放置过程被实施到扇形晶圆级封装生产流程中,证明自校准能够缓解该生产链中单个模具级步骤中扇形封装拾取和放置系统对机器人校准能力的严格要求。自对准过程进行了优化,失效模式,如不良的液体约束,表面污染,或过度的力被识别和消除。对于尺寸为3.1 mm × 3.1 mm的模具,每个点的键合精度均达到<3 μm @ 3 σ。使用平行模具处理,高速度每小时约10,000个单位是可能的。
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引用次数: 0
MAXQFP: NXP's new package solution for automotive application MAXQFP:恩智浦面向汽车应用的全新封装解决方案
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000015
C. Lee, T. Tran, A. Mawer, Xs Pang, J. Yao
172-lead (16x16 mm body size) and 100-lead (10x10 mm body size) MAXQFP's and 172 MAXQFP_EP (exposed pad) for automotive industry are introduced. The advantage of MAXQFP as compare to standard LQFP/QFP packages will be outlined. Thermal & mechanical simulation results were performed to prove its advantage over conventional LQFP and LQFP_EP. The challenges in manufacturing, designs and concerns of tighter lead pitches for MAXQFP are briefly addressed. Methods and data to resolve these challenges will be shown. For example, Sn whisker and Sn migration both are concerns to MAXQFP because of smaller distance between adjacent leads. The board-level solder joint reliability (SJR) has been collected to prove it is AEC G1 compliant. Visual inspection methods and requirements on AOI (automatic object inspection) systems on solider joints of J-leads of MAXQFP for are proposed. Standard AEC G1 component level reliability stresses defined at AEC Q100 which are TC (temperature cycling), HTSL (high temperature storage life), THB (Temperature Humidity Biased) and uHAST (un-biased HAST) tests are summarized Since Cu wires were used, AEC Q006 data are also collected. Assembly challenges are described. Future works will be summarized.
介绍了用于汽车工业的172引脚(16x16毫米车身尺寸)和100引脚(10x10毫米车身尺寸)MAXQFP和172 MAXQFP_EP(暴露垫)。与标准LQFP/QFP包相比,MAXQFP的优势将被概述。热力学仿真结果证明了该方法优于传统的LQFP和LQFP_EP。简要地解决了MAXQFP在制造,设计和更紧密的引线投球方面的挑战。将展示解决这些挑战的方法和数据。例如,锡晶须和锡迁移都是MAXQFP关注的问题,因为相邻导联之间的距离更小。已收集板级焊点可靠性(SJR)以证明其符合AEC G1标准。提出了MAXQFP j型引线焊接接头的目视检测方法及对AOI(自动对象检测)系统的要求。总结了AEC Q100中定义的标准AEC G1组件级可靠性应力,即TC(温度循环),HTSL(高温储存寿命),THB(温度湿度偏置)和uHAST(无偏置)测试。由于使用了铜线,因此也收集了AEC Q006数据。描述了装配方面的挑战。对今后的工作进行总结。
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引用次数: 0
A Novel Design of High-Temperature Lead-Free Solders for Die-Attachment in Power Discrete Applications 一种用于电源分立应用的高温无铅焊料的新设计
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000356
HongWen Zhang, Samuel Lytwynec, Huaguang Wang, J. Geng, Francis Mutuku, N. Lee
Development of high-temperature lead-free (HTLF) solders to replace high-lead solders for die-attachment in power device applications is driven by (1) the harmful effects of lead to human health and the environment, and (2) the demand of the improved bonding materials serving under high-power density and high-junction temperatures, especially for wide-band-gap power devices. A novel design, based on a mixed solder powder paste technology—Durafuse™—has been developed to deliver a Sn-rich HTLF paste, presenting the merits of both constituent powders. The combination of the rigid, high-melting SnSbCuAgX and the ductile, low-temperature Sn-rich solder in one paste enables reflow at a relatively low temperature (barely above the liquidus temperature of the final joint composition) and maintains the joint strength above 15MPa in the temperature range between 270°C and 295°C. The sufficient high-temperature strength has demonstrated the capability of maintaining the joint integrity during subsequent multiple SMT reflows below the 270°C peak temperature, regardless of the existence of a partial melting phase. Both X-ray inspection and cross-section microstructure have not shown any damage in the Si die or any noticeable cracks in the bonding joint, even after 3000 cycles of TCT (−40 to 150°C). In summary, Durafuse™ HT, the novel design of the high-temperature lead-free pastes, has shown the feasibility as a drop-in solution to replace high-lead solders for die-attachment in power discrete applications.
开发高温无铅焊料取代高铅焊料用于功率器件的模具连接,主要是由于:(1)铅对人体健康和环境的有害影响,以及(2)改进的键合材料在高功率密度和高结温下的需求,特别是用于宽带隙功率器件。一种基于混合锡粉膏技术durafuse™的新设计已经开发出来,可以提供富含锡的HTLF膏体,同时呈现两种成分粉末的优点。刚性、高熔点的SnSbCuAgX和延展性、低温富锡焊料结合在一个膏体中,可以在相对较低的温度(略高于最终接头成分的液相温度)下回流,并在270°C至295°C的温度范围内保持接头强度在15MPa以上。足够的高温强度证明了在270℃峰值温度以下的后续多次SMT回流中保持接头完整性的能力,无论是否存在部分熔化阶段。x射线检查和横截面显微结构均未显示Si模的任何损伤或接合处的任何明显裂纹,即使经过3000次TCT循环(- 40至150°C)。总之,Durafuse™HT是一种新颖的高温无铅浆料设计,作为一种可替代高铅焊料的解决方案,可用于电源分立应用的模具连接。
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引用次数: 0
Stabilized Sanathanan-Koerner Iteration for Rational Transfer Function Approximation of Scattering Parameters 散射参数有理传递函数逼近的稳定Sanathanan-Koerner迭代
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000171
Andrew Ma, Daniel Deaton, A. Engin
The vector-fitting algorithm has been the predominant method of macromodeling of high-frequency circuits for the past 20 years. Vector fitting is based on a partial-fractions basis to avoid the ill-conditioning of the Vandermonde matrices in direct fitting of the polynomial coefficients of a rational function. In a recent formulation of the Sanathanan- Koerner iteration, an orthogonal basis is obtained using the Arnoldi iteration significantly improving the conditioning and accuracy of rational approximation. This Stabilized Sanathanan-Koerner (SSK) iteration has been mostly applied on closed-form functions or data with no noise. We will utilize this SSK formulation for high-frequency package interconnect macromodeling. The method will be tested using empirical scattering parameters on a noisy transmission line system. The resultant curve fit will then be compared to several other polynomial and rational linear approximation methods, including the standard polynomial approximation. We show that the SSK method compares favorably to these different methods and provide a curve fit that can provide a reasonable approximation over different frequency ranges.
近20年来,矢量拟合算法一直是高频电路宏观建模的主要方法。向量拟合基于部分分式基,避免了Vandermonde矩阵在直接拟合有理函数的多项式系数时的不良条件。在Sanathanan- Koerner迭代的最新表述中,利用Arnoldi迭代获得了一个正交基,显著提高了理性逼近的条件和精度。这种稳定的Sanathanan-Koerner (SSK)迭代主要应用于封闭函数或无噪声数据。我们将利用这种SSK公式进行高频封装互连宏建模。该方法将在一个有噪声的传输线系统上用经验散射参数进行测试。然后将所得曲线拟合与其他几种多项式和有理线性近似方法(包括标准多项式近似)进行比较。我们表明,SSK方法优于这些不同的方法,并提供曲线拟合,可以在不同的频率范围内提供合理的近似值。
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引用次数: 1
Burn-in-Testing (BIT) Challenge: to BIT or not to BIT? 老化测试(BIT)挑战:要不要进行BIT测试?
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000031
E. Suhir
Burn-in testing (BIT) is a costly undertaking. Predictive modeling enables shading useful light on what and how should be tested, if at all. Three analytical (“mathematical”) predictive models recently suggested by the author are addressed in this mini-review: 1) A model based on the analysis of the infant mortality portion (IMP) of the bathtub curve (BTC) suggests that the non-random time derivative of the expected “statistical” failure rate (SFR) at the beginning of the IMP could be viewed as a suitable criterion (“figure of merit”) to answer the basic question of the BIT undertaking: “to BIT or not to BIT?” 2) A model based on the analysis of the random failure rate (RFR) of the mass-produced components that the manufactured product of interest is comprised of suggests that the above derivative is, in effect, the RFR variance of these components. 3) A model based on the use of the kinetic multi-parametric Boltzmann-Arrhenius-Zhurkov (BAZ) constitutive equation is employed to establish the BIT's adequate duration and level, if this kind of failure-oriented-accelerated-testing (FOAT) is found to be necessary. The theoretical findings are illustrated by calculated data. It is concluded that predictive modeling should always precede the actual BIT, that analytical modeling should always complement computer simulations and that future work should address the experimental validation and possible extension of the obtained results and recommendations.
老化测试(BIT)是一项代价高昂的工作。如果需要测试的话,预测建模可以为测试内容和测试方式提供有用的光照。本文讨论了作者最近提出的三种分析(“数学”)预测模型:1)基于浴缸曲线(BTC)婴儿死亡率部分(IMP)分析的模型表明,在浴缸曲线(BTC)开始时预期的“统计”失效率(SFR)的非随机时间导数可以被视为回答BIT承诺的基本问题的合适标准(“价值值”):“去BIT还是不去BIT?”“2)基于随机故障率(RFR)的分析模型,该模型表明,上述导数实际上是这些组件的随机故障率方差。3)如果发现有必要进行这种面向失效的加速测试(FOAT),则采用基于动力学多参数Boltzmann-Arrhenius-Zhurkov (BAZ)本构方程的模型来确定BIT的适当持续时间和水平。理论结果用计算数据加以说明。结论是,预测建模应始终先于实际的BIT,分析建模应始终补充计算机模拟,未来的工作应解决实验验证以及所获得的结果和建议的可能扩展。
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引用次数: 0
New approach for High Reliable & Cost-Effective Solder alloys for Automotive Applications 高可靠性和高成本效益的汽车焊料合金的新方法
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1.000159
S. Fritzsche, Manu Noe Vaidya, P. Prenosil, Katja Stenger, Jörg Trodler, M. Jörger
Commercially known as Innolot, the highly reliable lead-free alloy, allowing for high operating temperatures, is a Tin-Silver-Copper (SAC) metallurgical system with additional elements to harden the alloy and to improve its creep strength in order to significantly improve the reliability of solder joints. Compared to traditional SAC alloys, the characteristic lifetime can be enhanced on the base of temperature cycle tests (TCT) from −40°C to +125°C or even extended to 150°C. Assemblies in the automotive industry increasingly require higher reliability for safety relevant and emerging applications such as Advanced Driver Assistance Systems (ADAS). Cost-reduction requirements demand a new approach for optimized soldering processes and materials. As the current reflow process prefers Nitrogen atmosphere for low defects in high reliability soldering, our research focuses around the partial and/or complete change to air soldering processes. Furthermore, we investigate the influence of different surface finishes such as Chemical Sn, NiAu, and Cu OSP, and modified alloy compositions in the soldering performance. Apart from initial characterizations for various assemblies, reliability tests on Heraeus Reliability1 printed circuit boards as well as temperature cycle tests from −40 to +150°C for up to 2500 cycles are reported and resulting failure modes are discussed. This paper furthermore describes the potential for cost reductions via process and/or material optimizations without diminishing the high reliability performance for such automotive applications.
商业上被称为Innolot,高度可靠的无铅合金,允许高工作温度,是锡银铜(SAC)冶金系统,具有额外的元素来硬化合金并提高其蠕变强度,以显着提高焊点的可靠性。与传统SAC合金相比,在温度循环测试(TCT)的基础上,其特征寿命可以从- 40°C提高到+125°C,甚至延长到150°C。汽车行业的组件越来越需要更高的可靠性,以满足与安全相关的新兴应用,如高级驾驶辅助系统(ADAS)。降低成本的要求需要优化焊接工艺和材料的新方法。由于目前的回流工艺在高可靠性焊接中更倾向于氮气气氛,因此我们的研究重点是部分和/或完全改变空气焊接工艺。此外,我们还研究了不同表面处理(如化学Sn、NiAu和Cu OSP)以及改性合金成分对焊接性能的影响。除了各种组件的初始特性外,还报告了贺利氏可靠性1印刷电路板的可靠性测试以及从- 40°C到+150°C长达2500个循环的温度循环测试,并讨论了由此产生的故障模式。本文进一步描述了通过工艺和/或材料优化来降低成本的潜力,而不会降低此类汽车应用的高可靠性性能。
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引用次数: 0
Implementation of Trusted Manufacturing & AI-based process optimization into microelectronic manufacturing research environments 在微电子制造研究环境中实现可信制造和基于人工智能的工艺优化
Pub Date : 2021-10-01 DOI: 10.4071/1085-8024-2021.1
K. Becker, S. Voges, P. Fruehauf, M. Heimann, S. Nerreter, R. Blank, M. Erdmann, S. Gottwald, A. Hofmeister, M. Hesse, M. Thies, S. Mehrafsun, R. Fust, E. Beck, J. Pawlikowski, B. Schröder, C. Voight, T. Braun, M. Schneider-Ramelow
Digitization is one of the hot topics in all Industry 4.0 efforts that are currently discussed. Often the focus is on digitization of business processes with a financial/organizational perspective on manufacturing, so the tools are adapting to enterprise resource planning [ERP] and manufacturing execution system [MES] rather than on actual manufacturing issues on the shop floor. Within the SiEvEI 4.0 project, a research consortium from the area of electronics manufacturing is working on digitization for a manufacturing scenario where high value electronic goods are built in a distributed manufacturing environment. The key research topics addressed are the implementation of a Chain of Trust [CoT] for such a distributed manufacturing, i.e. and the application of artificial intelligence/machine learning to analyze and eventually optimize manufacturing processes. The paper will introduce the concept of both COT and AI-based process analysis that will later on transferred into a microelectronics production environment. Two reference processes are targeted, SMD assembly using fully automated manufacturing equipment and Solder Ball Application using a high-mix/low volume concept. As a result, the paper presents a concept of how to digitize manufacturing processes and use this digital description of a process combination to make a distributed manufacturing flow safe and increase product/process quality.
数字化是目前讨论的所有工业4.0努力中的热门话题之一。通常,重点是业务流程的数字化,从财务/组织的角度来看制造,因此这些工具适应企业资源规划[ERP]和制造执行系统[MES],而不是车间的实际制造问题。在SiEvEI 4.0项目中,来自电子制造领域的一个研究联盟正在研究在分布式制造环境中制造高价值电子产品的制造场景的数字化。关键的研究课题是为这种分布式制造实现信任链,即应用人工智能/机器学习来分析和最终优化制造过程。本文将介绍COT和基于人工智能的过程分析的概念,这些概念随后将转移到微电子生产环境中。有两种参考工艺,采用全自动制造设备的SMD组装和采用高混合/低批量概念的Solder Ball应用。因此,本文提出了如何将制造过程数字化的概念,并利用这种过程组合的数字化描述使分布式制造流程安全并提高产品/过程质量。
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引用次数: 0
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International Symposium on Microelectronics
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