We built co-packaged optics modules having polymer waveguide fiber interfaces successfully. We tested two types of assembly orders with Photonic-Integrated-Circuit (PIC) to Polymer Optical-Waveguides (PWG) first and PIC to PWG last. We characterized optical link performance before and after reflow, which indicated flip chip & BGA reflow compatibility. Full module build hardware underwent reliability pre-conditioning and then underwent JEDEC reliability stress testing, including (1) deep thermal cycling, (2) low-temperature storage, (3) high-temperature storage, and (4) high temperature and high humidity test followed by characterization. We evaluated the optical link loss of PIC to PWG to Ferrule assemblies using twelve channels per PIC with a 50-micrometer pitch at the PIC to PWG interface. Feasibility of further reduction of this pitch to less than 25 micrometers has been shown using modeling and prototype polymer waveguide hardware. This polymer optical waveguide method allows to support chip and optical waveguide bandwidth density up to 12 times larger compared to the case using standard v-groove single mode fiber interconnection.

We report on the successful design and fabrication of optical modules using a 50 micron pitch polymer waveguide interface, integrated for low loss, high density optical data transfer with very low space requirements on a Si photonics die. This prototype module meets JEDEC reliability standards and promises to increase the number of optical fibers that can be connected at the edge of a chip, a measure known as beachfront density, by six times compared to state of the art technology. Scalability of the polymer waveguide to less than 20 micron pitch stands to improve the bandwidth density upwards of 10 Tbps/mm.

A novel adhesion method of a sensor to a fingernail is described. Wearable sensors can provide health insights to humans for a wide variety of benefits, such as continuous wellness monitoring and disease monitoring throughout a patient's daily life. While there are many locations to place these wearable sensors on the body, we will focus on the fingertip, one significant way that people interact with the world. Like artificial fingernails used for aesthetics, wearable healthcare sensors can be attached to the fingernail for short or long time periods with minimal irritation and disruption to daily life. In this study the structure and methods of healthcare sensors' attachment and removal have been explored to support (1) the sensor functional requirements, (2) biological and environmentally compatible solutions and (3) ease of attachment and removal for short- and long-term user applications. Initial fingernail sensors were attached using a thin adhesive layer of commonly available cosmetic nail glue. While this approach allowed for easy application and strong adhesion to the nail, the removal could expose the fingernail and finger to a commercially available cosmetic nail removal (acetone-based chemical) for extended times measured in minutes. Therefore, a novel structure and method were developed for rapid healthcare sensor attachment and removal in seconds, which supported both the sensor functional objectives and the biologically and environmentally safe use objectives.

Multiple moisture evolutions/adsorptions pathways on the dielectric film surfaces and in the film bulk were linked to bonding voids contributions based on Zhuravlev model in silica. A die-to-die (DtD) and die-to-wafer (DtW) Cu/interlayer dielectric (ILD) hybrid bonding methodology has been successfully developed to reduce and eliminate moisture related voids with defect-free results.

Silicon (Si) handle technology benefits that support advanced chiplet technology applications include: (1) semiconductor process and equipment compatibility, (2) improvement on heating/cooling rates with reduced stress and wafer warpage and (3) contamination avoidance. This paper reports the next generation Infrared (IR) laser debonding technology to release Si handler from 300mm advanced CMOS nodes wafer with or without TSVs. IR laser systems with Gaussian and Top-Hat beam profiles were used to study the laser ablation characteristics on different families of release layers and bonding adhesives. Post wafer debonding, a wafer cleaning process was developed, and the IR laser impacts on passive and active device wafers were studied with physical and electrical tests. The results indicated the optimization of physical structures and IR laser control parameters were critical to achieve quality release for chemical stripping and compatibility with subsequent integration. This IR laser debonding technology continues to successfully support ongoing 2.XD and 3D fine pitch I/O chiplet test vehicle build and integration demonstrations with micropillar solder bonding or Cu-Cu / ILD Hybrid bonding.

The characteristics and quality of the bonding interface in hybrid bonding vary greatly depending on physical and chemical factors during the bonding process. Quantitative understanding and evaluation of the surface energy of the bond are essential to improve reliability. While destructive razor blade testing has been commonly used to quantify the surface energy and interface toughness in wafer-level bonding for years, there is currently no standard quantitative method for evaluating die-level direct bonding. In this study, the displacement control of single-beam cantilever (SBC) was specially developed as a new quantitative characterization method to evaluate the surface energy at the die level. For this characterization test, we first used a 10 × 10 mm2 die size with controlled bond surfaces, followed by a 6.3 × 10.3 mm2 Cu hybrid bonding sample with an array of Cu bond pad size of 6 μm in diameter and 12 μm pitch. The pre-bonding process (wafer protection, dicing, cleaning, and surface activation), and die-level bonding methods were evaluated using this new characterization method. Process optimization resulted in die-level bonding consistency with surface energy higher than 2.0 J/m2, and voids-free bonding.

In Co-Packaged Optics (CPO) where optical devices and ICs are attached to a common base substrate, there are requirements to keep the temperature of high-heat-dissipating ICs as low as possible and also to keep the temperature of optical devices constant. We propose two solutions to meet these two requirements and show the effect of two solutions by simulation.

Handwriting was since the start of the history, a higher expression of human skills, and was used for documentation of experiences, and for communication. Existing writing technology require a writing tool, like a pen, and a dedicated writing surface, like paper, or more recently an electronic tablet. These accessories of writing, of writing tool and service, are not available in many daily life situations. Furthermore, the writing accessories, are not natural, in many cases are not ergonomic, and thus can cause fatigue, and in extreme cases contribute to muscular and neurological diseases. In this work, we suggest to step back in history and step forward in technology, and to create, for the first time, an alternate writing solution without any accessories, using one own finger as writing tool, and write on almost any surface. For this, we used directional pressure sensors attached to the fingernail. Changes in the pressure induced on the fingertip in different directions while writing, are projected to the fingernail, and then assessed as a voltage pattern by the sensor. Decoding the pattern, can reveal symbols like letters, punctuations, and writing commands. In this paper, we describe the new pressure sensing modality and tailor processing methods. We tested the new technology on two subjects having different writing patterns while writing alphabet and sentences on different surfaces. We reached letter detection of over 80% while writing on a table, and the word detection rate, was near 70%, after applying the correction algorithm include language priors. The results of this work can revolutionize the way people write and communicate using more convenient, and more approachable, finger-tip writing.

In this work, a panel packaging approach based on programmable laser milling, injection molded soldering (IMS), and temporary handling technologies has been proposed and demonstrated for micro thin-film-battery (TFB) cells. Micro TFB cells in the dimensions of 2.5mm × 2.5mm × 0.1mm have been successfully packaged and sealed with overmolding solder.

This paper describes the sensor, electronics, software, modeling, and characterization of a fingernail-mounted RF-connected wearable strain sensor system that measures nail deformation from finger movement. Applications to health monitoring and human computer interfaces in homes, hospitals, and workplaces are discussed. The mechanical deformation of a fingertip pressed or drawn against a plate is demonstrated using a three-dimensional finite-element linear-elastic model to predict the signal level, optimum sensor locations and the type and location of deformation expected for different finger motions. The 3D finite-element linear elastic model is derived from X-ray images of a human finger but generalized and parameterized to allow new models to be created by scaling internal and external parameters such as skin thickness and nail and finger shape to predict sensor system performance for a more general human population. Our analysis finds that a single sensor mounted in the center of the nail will respond to typical grip pressures on the fingertip with readily detectible strain amplitudes but that a multi-sensor array will be sensitive to more general haptic phenomena such as the direction and magnitude of frictional loads and loading of the distal phalangeal joint. It is shown that depending on finger use and loading the nail exhibits shifts in direction, location and sign of strain over the fingernail surface. Measurement data from a simple multi-sensor array is shown to be useful in distinguishing between load conditions, however additional sensors are required for full determination.

In this work, a novel packaging structure has been demonstrated for micro-TFB cells. Various semiconductor fabrication and assembly processes have been applied to thin substrate via formation and sealing, micro-TFB singulation and handling, as well as metallic sealing for hermetic battery packaging. Micro-TFB cells in the dimensions of 2.5mm x 2.5mm x 0.1mm have been fabricated and tested. A normalized capacity of similar to 190 pAh/cm(2) has been demonstrated.

A novel writing platform composed of a wearable sensor on the fingernail and classification algorithms is described. Findings from using this platform to translate fingertip writing into shapes, letters, and numbers on a range of surfaces are reported. The new wearable platform leverages an architecture with miniaturized electronic circuitry to precisely measure a set of forces in the longitudinal and transverse directions using multiple strain gauges. We find that the directional pressure patterns are translated from the fingertip to the fingernail. Deformation of fingernails in the longitudinal and transverse directions are detected by the fingernail sensor which sends the data wirelessly to a portable electronic system. Fingernail pressure patterns are categorized through signal processing to recognize a range of shapes, numbers, and letters, enabling fingertip writing recognition. Use of the writing platform following a short training session, shows human fingertip writing on multiple surfaces were automatically transcribed to a computer.

Wearable sensors can provide important human physiology and activity data and therefore have promising applications in healthcare, entertainment, and security. Here, we report the design, fabrication, and characterizations of a thin silicon film sensor for wearable sensor applications. Temperature, light, and strain sensing capabilities of the thin film of doped silicon, fabricated using a controlled spalling process, were fully characterized. An n-doped silicon thin-film sensor prepared with the spalling technology exhibited a temperature coefficient of -0.44%/degrees C. The sensor also showed excellent light sensin response in an illumination range from 110 to 1710 cd/mm(2). The ratio of the electrical resistance changes over the applied forces was measured to be around 0.6%/N.

Innovations in healthcare, diagnostics, sensors and data analysis with Artificial Intelligence (AI) learning / recommendations offer opportunities for improved personalized healthcare, lower costs and benefits to the medical industry. The age of personalized human health monitoring has begun. Human health monitoring using fluidic diagnostic monitoring, non-invasive sensors, wearables (electronic health sensors), implanted health sensors, sound, visual images, and combinations of these data trends offer individuals personalized healthcare guidance. The data, analytics and recommendations from these personalized solutions are beginning to aide our early detection and understanding of health risks from chronic diseases and overall health / wellness. Examples include: cardiovascular disease, diabetes, oncology / cancer, kidney disease, elder care, Parkinson / Huntington Diseases, and many other healthcare applications. Rapid advancements of innovative healthcare diagnostic tools, health and environmental sensors along with data trending and analysis using AI systems or platforms can provide industry disruptions in healthcare. AI systems already aid health professionals and individuals with knowledge and recommendations that offer the promise of improved quality of life and lower healthcare costs. Examples such as: (1) earlier chronic disease detection and potential for disease progression delay or prevention, (2) understanding individual behavior, medication treatments and effectiveness of the treatments on activities of daily living and (3) personalized care based on your DNA, medical diagnostics and your healthcare trends relative to your healthcare needs and options to manage your quality of life. In this paper, we describe both new technologies and advancements to heterogeneous integration technology tools, materials and processes that provide differentiating electronics for future healthcare diagnostic tools and sensors. These new technologies are being applied to targeted applications in healthcare diagnostics and sensor monitoring for precision diagnostic data, smaller product size and much lower costs. Data streams can leverage AI to provide smart personalized healthcare guidance or solutions that compliment existing technology and data to partners such as healthcare professionals, patients and clients. In many applications, we leverage industry available technology or benefit from these new technology advancements to provide for the best system solution. Examples of these new and advancing technologies include: (1) Precision handling thinned wafers with large die, small die, multi-die, sub-components, components and substrates technologies, (2) Injection molded solder (IMS) technology for wafers (TSV and / or interconnection) and substrates, (3) Precision micro-component, die, multi-die substrate and multi-component assembly / integration technology for healthcare, IoT and AI Systems, (4) Precision laser micro-machining, cutting and welding technology, (5) Flexible multi-channel, micro-fluidic systems for smart sensing, point of care (POC) diagnostics, and AI and (6) Small form factor micro-systems and energy solutions / technologies that support future healthcare, IoT, and AI linked computing solutions. Examples of key challenges and advantages of these technologies for the targeted applications are shared relative to current industry standard solutions. Highlights on future demonstrations in progress at the time of writing this paper are targeted for our 2018 ECTC presentation and other future technical publications.

We developed a tool of molten solder injection which is able to form solder bumping on wafers, ceramic/organic substrates, flexible circuits, and Si via filling from fine pitch to large pitch. One tool has capabilities of solder bumping on wafers from 15 microns diameter to larger than 1000 microns diameter, bumping on organic substrates from flip chip pre-solder to BGA size, soldering on flexible circuits with <; 25 microns width of circle and square shape, and via filling of Si wafer with various via diameters. Also, this tool enables the change of solder composition to be very easy and fast because simple switch of the solder injection head allows to change the solder composition like switching an ink cartridge in an inkjet printer. The solder injection tool head contains a reservoir of molten solder of desired composition and a slot through which the molten solder is injected with an optimized combination of pressure and temperature. The solder injection slot of the head is configured in the portion of compliant material and low friction material such that this combination provides good wiping characteristics as well as allowing the IMS head to better track surface topography of an organic substrate. This paper will review key attributes of the molten solder injection tool and discuss differences in the processes required for each different applications of solder bumping on Si wafers and ceramic/organic/flexible substrates as well as filling solder into Si vias. We will describe data of 200mm wafer bumping results with different bump diameters and shape, solder bumping results on organic and ceramic substrates, soldering on flexible circuits, and via filling results of Si. Also, solder alloy flexibility of this technology has been demonstrated from low melting temperature Pb-free solders to high melting temperature Pb-free solders.

This paper proposed a high-speed precision handling technology of micro-chip using programmable laser debonding technology for fan-out wafer level packaging (FOWLP) application, and investigated the programmable capability, the speed and the accuracy with laser debonding experiments on chips down to 25umX25um. The proposed FOWLP approach has features of: (a) all steps are based on wafer-level processes by using programmable laser debonding technology to achieve the reconstituted wafer, enabling high-speed precision hanldinghandling technology for micro-chip. And, (b) two bonding interface layers, one high-strength adhesive layer for chips firmly joined to handler and the other UV-sensitive layer for easily laser debonding, can improve the die-shift issues. The successfully debonding results, including selectively debonding 200umX400um chips from handler wafer and specifically debonding 25umX25um chips forming the letters "IBM", indicates the programmable capability of this technology. The experiment results show that the debonding speed can be up to 360,000 components per hour (cph), and the debonding accuracy can be in the microns range.

In this research study, we present comprehensive characterizations of flexible silicon sensors fabricated using controlled spalling which uses fracture to produce thin films of single-crystal silicon directly from a bulk substrate. We characterized the property of the thin silicon film for sensing strain and temperature. The flexible sensor exhibits high sensitivity with a temperature coefficient of resistance of -0.16/°C, which is desirable for targeted health monitoring applications.

IBM Research and Micro-System Technology and Solutions Team are enabling next generation computing systems with heterogeneous packaging integration that support both large size / high performance systems and also support miniaturized / low power mobile wireless systems / sensors.