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The document titled "DEVICE PACKAGING 2024" provides a schedule or program for a conference or event related to microelectronics and device packaging. It includes a list of professional development courses (PDCs) led by industry leaders, keynote sessions, technical sessions, and a member's event organized by 3D InCites. The topics covered in the PDCs and technical sessions range from fan-out wafer level packaging to chiplet design and 5G/6G/mmWave materials. The document also lists posters and presentations on various topics such as secure track and trace in microelectronics, thermal optimization of embedded MOSFET, and 2.5D/3D packaging market trends. [Extracted from the article]

The semiconductor industry is driving to enable high volume integration of disparate die types via heterogeneous integration (HI). These die can come from a range of wafer sizes fabricated in different technology nodes. This emerging package type creates new challenges regarding assembly efficiency and yield. Traditionally, flip-chip assembly process flows have utilized a single placement tool for the placement of the single die type onto the target substrate. For applications with multiple die types, a series of placement tools have been configured in a production line, with each tool dedicated to the placement of a specific die type. This paper and presentation explore the implications of this type of solution in the era of HI. Impacts on product yield, throughput, manufacturing efficiency, and overall cost of assembly will be explored for a broad range of HI die configurations. Based on a sensitivity analysis for the range of die types expected in these applications, a novel approach to optimization of overall assembly economics will be proposed. The appropriateness of this novel approach will be explored for a range of packaging solutions, including flip-chip, 2.5D, 3D, and fan-out. [ABSTRACT FROM AUTHOR]

Immersion tin finishes are widely used in the printed circuit board (PCB) industry. They provide reliable connections with high solder joint reliability compared to other final finishes. Due to the direct intermetallic formation between copper and solder, the intermetallic compounds (IMC) formed during the assembly exhibit ductile properties and are less prone to brittle fractures than e.g., solder joints formed with nickel finishes such as electroless nickel/immersion gold (ENIG). With the given high solder joint reliability, the immersion tin finish therefore is one of the first choices for the application in the IC substrate industry. It provides already a robust and nickel free finish with high process efficiency for lower cost. But due to the trends to increased I/O counts, reduced lines and spaces, improved signal integrity and further lowering the cost in the packaging applications, the adjustment of the immersion tin process became necessary to cope with the changed technology demands. Topic of this paper is the introduction of an immersion tin plating process specifically designed for IC substrate applications. It is focusing on three major aspects: the plating process itself, the equipment solutions to realize best quality control and process monitoring and finally the performance of the final finish itself in comparison to other common end finishes. The trend to more and more reduced lines and spaces requires the adjustment of the plating chemistry. A good solution flow needs to be ensured to prevent excessive attack of the copper tracks or disproportionate solder mask undercut. The study presented here compares conventional immersion tin plating solutions with a modified process for IC substrate plating. It shows, how the variation of solution viscosity and flow can impact the copper attack and solder mask undercut. Due to the better solution exchange and adjusted plating conditions, the copper dissolution can be significantly reduced and the attack to the solder mask can be minimized. The complimentary horizontal plating equipment supports the specific properties of the plating electrolyte. Insights to the equipment design and adjustments are being discussed to identify the best conditions for the immersion tin plating on fine structures with highest quality demands. Finally, the tin deposit is investigated and compared to conventional immersion tin as well as to other standard finishes such as ENEPIG (Electroless Nickel, electroless Palladium, Immersion gold) or OSP (organic solder preservative) regarding its solder wetting performance and solder joint reliability. It can be concluded that the immersion tin finish designed for small L/S applications can validate the benefits known from the long years' experience with immersion tin. The layer shows comparable solder wetting properties to conventional immersion tin finishes and excellent solder joint reliability when compared to ENEPIG or OSP with better performance even after thermal aging. The risk for typical IC substrate related defects such as excessive copper corrosion or solder mask undercut as well as missing bumps is lowered compared to the conventional process. The main focus of this paper is to show, that the high demands in substrate industry can be tackled when the plating solution and plating equipment are designed and adjusted to the new requirements in a coordinated approach so that they can complement each other. [ABSTRACT FROM AUTHOR]

DuPont has developed new Photo-Imageable Dielectrics (PID) to complement its existing permanent bonding materials. The CYCLOTENE™ family of dielectric materials are well known for use as a permanent dielectric and have seen significant use in commercial applications including BSI CMOS image sensors, integrated passive devices, and as optical bonding adhesives. For new applications, there is a desire to have a thermal stable material that can be patterned to eliminate the material from the metal joining region or from the light path. We will demonstrate in this paper that the solvent developed PID as well as our existing aqueous developable PID are both capable of wafer-to-wafer bonding after photo imaging and development. In addition to bonding using a commercial wafer to wafer bonding tool, we have shown that W2W bonding is achievable using a two-stage vacuum laminator. Optimization of the curing process will be discussed to prevent any separation or reflow of the PID as well as achieving the maximum adhesion energy after full cure. In the future, we will show the use of the negative tone PID as a solder collar or polymer dam to enable high density flip chip bonding using 15μm Sn/Ag capped copper pillars with a 1:1.5 pitch to a and 18μm polymer openings with a 1:1.08 pitch in 10mm x 10mm dies as well as outline the process we will use to extend this approach to Cu-Cu hybrid bonding. [ABSTRACT FROM AUTHOR]

We present a very compact hybrid detection module based on an advanced liquid-cooled low temperature cofired ceramic (LTCC) substrate. The double sided hybrid combines 144 photo detectors and four specialized flip chip readout ASICs (Application Specific Integrated Circuits) used for the readout of scintillation crystals with application in time-of-riight positron emission tomography (PET) combined with magnetic resonance imaging (MRI). If MRI images and PET images are combined, completely new medical diagnostic and treatment prospects are feasible because the two techniques are complementary and they will offer both anatomical and functional information. One of the biggest challenges is the development of miniaturized detector modules that are highly functional and MRI compatible. Our SiPM (Silicon Photomultiplier) module has an area of 32.8 by 32.0 mm2 and contains 12 x12 SiPMs in a pitch of 2.5 mm2. The SiPM readout of the 144 channels is performed by four PETA6 ASICs. The LTCC substrate with a 2.1 mm thickness has been manufactured using the most advanced technologies developed at Micro Systems Engineering GmbH. To guarantee the manufacturability in serial or mass production, DP951 P2 green tape has been used. For the cooling channels, special technology has been developed by MSE. The liquid cooling channels inside the LTCC substrate provide excellent cooling for the ASICs, the SiPMs, and thermal insulation between ASICs and SiPMs and allow a very compact design of the detector modules, reducing their height by 50% compared with other technical solutions. We can insert a ring of our modules in an existing MR (Magnetic Resonance) scanner. Operating the SiPMs at low temperature improves their performance, reducing the effects of dark count rate and improving image quality. There is no heatsink, heat pipe, or other cooling element attached to the back side of the ASICs. To avoid interference between the PET and MRI system, short signal length is required for minimizing pickup loops and eddy currents. The 12 SiPM arrays with 2x6 geometry are wire bonded only at the edges of the SiPMs to the LTCC, enabling the use of nearly the whole detector area for photon detection, which is of paramount importance for excellent image quality. At the opposite side of the substrate, four ASICs with 272 µm bump pitch are flip chip solder assembled to the LTCC substrate including underfilling, and a few SMD (Surface Mount Device) components are mounted. A scintillator crystal array on top of the SiPMs converts gamma rays (511 keV photons produced from positron-electron annihilation) into light. We assume that the LTCC substrates and all components are fully MRI compatible, which is important for the integration of PET with MRI without mutual interference. The paper elucidates the impact of the used technology on the performance of advanced PET/MRI detector modules. [ABSTRACT FROM AUTHOR]

Advanced packaging technologies have increased in complexity over the years, transitioning from single to multi-die packaging, enabled by 3-dimensional (3D) integration, System in Package (SiP), Wafer Level Packaging (WLP), and increasingly creative approaches to embedding die. These new innovative packaging technologies enable more functionality and offer higher levels of integration within the same package footprint and often in an intensely reduced footprint. In fact, the latest advancements in heterogeneous integrated semiconductor packaging are able to provide reduced form-factor, increased data transfer rate and improved signal integrity and memory bandwidth, all with reduced power and improved thermal performance. In today's connected world with the proliferation of connected devices forcing continually higher system-level performance, semiconductor packaging has stepped up to play a pivotal role in providing solutions to the newest system-level requirements. To further compound the semiconductor packaging challenge, the continued scaling of transistor geometries for semiconductor devices further increases the demand on next-level interconnect technologies. Heterogeneous integration of memory, logic, and power management devices is increasingly becoming the norm for next-generation mobile, high-performance graphics, and network applications. This requires advanced packaging technologies with capabilities for very high signal routing densities, efficient power distribution, and superior signal integrity. In addition, 3D package integration is often required, especially for mobile applications. This places an increased emphasis on the package technology's z-height reduction and thermal performance capabilities. Traditional organic laminate substrates that utilize flip chip bonding have met the semiconductor industry's advanced interconnection needs for over 15 years. With continued advancements in materials and processes, laminate substrates are expected to satisfy the majority of advanced package performance and cost requirements for years to come. However, feature-size limitations and electrical and thermal performance constraints will continue to restrict laminate substrates from meeting the integration requirements for next generation mobile and networking applications. Emerging silicon-based interconnection technologies, such as through silicon via (TSV) have shown promise in this area. By leveraging the back end of line (BEOL) damascene processes of the wafer fab, multi-layer sub-micron signal trace densities can be achieved. However, supply chain limitations and intrinsic cost implications have limited the proliferation of 3D IC technology. In particular, for silicon interposers, there can be an undesirable effect to z-height and electrical performance due to the inherent thickness and parasitics of the silicon interposer. This paper will discuss innovative wafer fan-out technologies that meet the heterogeneous integration requirements for an increasingly connected world, bridging the gap between organic laminate-based substrates and inorganic foundry-based silicon interconnect solutions. [ABSTRACT FROM AUTHOR]

Heterogeneous integration of logic, memory, and sensor chips on interposers (2.5D) has attracted a lot of attention as a candidate for More-than-Moore technology. For high performance 2.5D devices, high density integration of chips with narrow spacing and high density interconnections with small pitch bonding electrodes are a key technology. In the current bonding technology, solder micro-bumps (>20 μm in diameter) and non-conductive adhesives have been adopted. There may be some limitations for high density device integration with these technologies because of the protrusion of adhesives around the chips, the thermal sliding at the bonding, and the limit of solder micro-bump minimization. Hybrid bonding with a small Cu electrode (<10 μm in diameter) is a strong candidate for improving advanced device integration technology. Our goal is to develop a new adhesive which gives no protrusion, no thermal sliding, no voids, and high electrical reliability. A spin coating thin adhesive was therefore developed. The new adhesive can be cured at 200 °C. The cured adhesive film has no tackiness and has an optically flat surface. The adhesive film can be temporarily bondable to SiO2 at room temperature. After 200 °C baking, a permanent bonding can be achieved, and there is no degradation of bonding strength and no voids even after 400 °C of baking. For the applicability to the chipon- wafer process, the adhesive film/Si wafer can be cut into chips by blade dicing without any delamination and without any apparent particles. After bonding the adhesive/Si chip to a bare Si wafer at room temperature, the thermal sliding amount after the thermal compression process (250 °C, 10 min, 1 MPa) was less than 1 μm (under the detection limit) according to optical microscopic measurements. In addition, there was no protrusion of adhesive around the chip corner from SEM. A first trial result for hybrid bonding is also reported. [ABSTRACT FROM AUTHOR]

The article discusses the innovations of mobile electronics with the development of copper pillar packaging technology. It notes that copper pillar bump technology offers low profile and small area packaging in fine pitch flip chip in mobile devices. It highlights the continued development of early flip chip in chip-scale package (CSP), ball grid array (BGA) and package-on-package (PoP)platforms with the ability to integrate copper pillar inteconnect.

The article discusses solution for ultra-fine pitch flip chip featuring advantages of thermocompression bonding including high accuracy, warpage and stress, and traceability.

The industry has witnessed the adoption of flip chip for its low cost, small form factor, high performance and great I/O flexibility. As the Three Dimensional (3D) packaging technology moves to the forefront, the flip chip to wafer integration, which is also a silicon to silicon assembly, is gaining more and more popularity. No flow underfill is of a special interest for the wafer level flip chip assembly as it can dramatically reduce the process time and the cost per package, due to the reduction in the number of process steps as well as the dispenser and cure oven that would be otherwise necessary for the standard capillary underfill process. This paper introduces the development of a no flow underfill process for a sub-100 micron pitch flip chip to CSP wafer level assembly. Challenges addressed include the no flow underfill reflow profile study, underfill dispense amount study, chip floating control, underfill voiding reduction and the yield improvement. Also, different no flow underfill candidates were investigated for the best performing processing material. [ABSTRACT FROM AUTHOR]

The article examines the basic structure of flip chip interconnect in microelectronics packaging in the U.S. It states that the flip chip interconnect can be found in wireless products which include central processing unit (CPU), graphic processors (GPUs) and Application Specific Integrated Circuits (ASIC). It also notes the use of through silicon via (TSV) technology on game machines of some companies.

The article discusses the history of electroplating for bumping and wafer level packaging. It states that the research of Fumio Nakano and Yutaka Tsukada opened the possibilities for the use of the flip chip technology on less costly substrates and wide number of applications. It cites that in the decade of 2000, the use of flip chip and wafer level packaging has grown. It also mentions that electroplating is an indispensible part of wafer level package fabrication.

The article offers information on the history of flip chip and wafer level packaging (WLP). It mentions the use of flip chip packaging in the 1960s by International Business Machines corp. (IBM) to automate the assembly of semiconductor and improve its reliability. It notes that flip chip is adopted in the late 1990s to improve power and ground distribution. It also emphasizes the development of wafer level package technology in early 1997 by Flip Chip Technologies LLC.

This article investigates a new pressure measurement method usable during packaging of electronic systems. With pressuresensitive multilayers it is possible to determine the pressure distribution on the surface of mold cavities and on various electronic substrates during packaging processes. The pressuresensitive multilayer is based on commercially available surface pressure indicating fi lms such as Fuji Prescale®1 (www. sensorprod.com) that change color directly proportional to the amount of pressure applied. Homogenous pressure distribution within the molding cavity is of particular importance for encapsulation of mechanically sensitive electronic components, e.g., MEMS sensors, bare dies and Flip Chips. With the implementation of specially multilayered sensor fi lms, a fast estimation of the pressure distribution within the cavity will be possible. We successfully used the new sensor concept to investigate industrial transfer molding processes with epoxy molding compounds (EMC). On distinct points of the mold cavity conventional piezo pressure sensors have been applied to get a time-dependent pressure signal. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including flip chip technology, electroplating for bumping and wafer level packaging (WLP), and fan out WLP (FO-WLP) in embedded die.