Temporary Bonding of Wafers, Displays, and Components

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 1-68
Author(s):  
John Moore ◽  
Jared Pettit ◽  
Alex Brewer ◽  
Alman Law
Keyword(s):  
Printed Electronics ◽  
Adhesion Force ◽  
Substrate Surface ◽  
Adhesive Force ◽  
Flexible Displays ◽  
Substrate Removal ◽  
Solder Bumps ◽  
Silicone Polymers ◽  
Temporary Bonding ◽  
Industry Needs

Packaging practices are conducted on work unit substrates while they are temporarily held in place. This requires a simple adhesion process that enables easy removal without the burdens of complex cleaning. Substrates may be wafers, flexible displays, or components, organic or inorganic, and may contain topography such as solder bumps. The choice of a temporary bonding medium is dependent upon its ability to resist exposure to heat and chemicals. Thermal resistant materials as polyimide (PI), bisbenzocyclobutene (BCB, DOW CycloteneTM), or silicone can support processes that exceed 300°C, depending upon exposure conditions. In building flexible displays, PI materials are popular choices as a substrate processed from liquid and film forms. [1] These products may use silicone polymers, providing low outgas and inert character with an adhesive force tuned to allow substrate removal by peeling without a loss of integrity. Similar approaches are used for discrete, thin, fragile components, attached by dry bonding, processed, and removed by simple peeling practices without observed residue. Examples of die temporary bonding include encapsulation during bumping, permanent bonding, or vacuum deposition of EMI/RFI shielding. [2] The success in these and other technologies depend upon the use of the proper adhesive but most importantly, the tuning of the adhesion force. Successful tuning depends upon many factors, including substrate surface energy, texture, and the bonding process. Daetec has created adhesives used in temporary bonding processes for nearly 20yrs, applying to multiple wafer types, OLED and TFT displays, printed electronics, solar, thinning down to 4um, and thermal resistance >600°C. [3] Our experience in creating solutions for these and other industry needs will be discussed as well as the criteria to temporarily support flexible and rigid substrates of all types, sizes, and shapes.

Substrate Temporary Bonding Supporting Post-Processing Applications

2015 ◽  
Vol 2015 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Jared Pettit ◽  
Alman Law ◽  
Alex Brewer ◽  
John Moore
Keyword(s):  
Physical Vapor Deposition ◽  
Printed Electronics ◽  
Adhesion Force ◽  
Substrate Surface ◽  
Chemical Diffusion ◽  
Adhesive Force ◽  
Post Processing ◽  
Flexible Displays ◽  
Substrate Removal ◽  
Temporary Bonding

Post-processing applications are carried out on substrates while they are temporarily supported. This requires a simple adhesion process with easy removal without complex tooling or cleaning. Substrates include wafers, displays, or components, organic or inorganic, and may contain topography such as solder bumps. The applications may vary from backside processing of wafers, complete flexible circuit integration, or the stacking of packages. Simple processing may use green products as the detergent soluble DaeCoatTM 600-series, exhibiting thermal stability from 80°C to allow hot DIW debond, to over 200°C to support thermal processing. Temporary bonding may resist heat and chemicals for many steps or one major extreme. The DaeCoatTM 300-series of products are designed to resist thermal exposures >300°C for wafer operations with bumps or reach ≥400°C (DaeCoatTM 315) for flexible displays to allow casting of liquid polyimide (PI) [1]. The properties are consistent with the needs of electronics processes, providing outgas below 1% inert to fab chemicals, and most important, an adhesive force that is tuned to allow simple substrate removal (peeling, lifting, or chemical diffusion). Where discrete die or components require installing infrastructure to support stacking or fan-out designs, the thin and fragile substrate is securely held in place by simple dry bonding completed in seconds and later removed by similar peeling practices without observed residue. Such component practices enable encapsulation during bumping, permanent bonding, or physical vapor deposition (PVD) of electromagnetic and radio-frequency interference (EMI/RFI) shielding [2]. The success in these and other technologies depend upon the use of the proper adhesive but most importantly, the tuning of the adhesion force. Successful tuning depends upon many factors, including substrate surface energy, texture, and the bonding process. Daetec has created adhesives used in temporary bonding processes for nearly 20yrs, applying to multiple wafer types, OLED and TFT displays, printed electronics, solar, thinning down to 4um, and thermal resistance >600°C [3]. Our experience in creating solutions for these and other industry needs will be discussed as well as the criteria to temporarily support flexible and rigid substrates of all types, sizes, and shapes.

Implementation of Flexible Displays for Smart Textiles Using Processes of Printed Electronics

2019 ◽  
Vol 2019 (NOR) ◽  
pp. 000021-000028
Author(s):  
Artem Ivanov
Keyword(s):  
Comparative Analysis ◽  
Field Test ◽  
Light Emitting Diodes ◽  
Printed Electronics ◽  
Comparative Investigation ◽  
Manufacturing Processes ◽  
Smart Textiles ◽  
Flexible Displays ◽  
Light Emitting ◽  
Driver Electronics

Abstract Utilisation of light emitting diodes (LEDs) and printed electroluminescent elements for manufacturing of flexible displays to be integrated in textile items was analysed. The comparative investigation focused on the necessary manufacturing processes, on the architecture of driver electronics, on achievable display brightness, on lifetime expectations and reliability aspects of the systems. Printed electroluminescent display demonstrators were manufactured and integrated in jackets for the currently running field test. Description of the produced systems as well as the results of the comparative analysis are presented.

High Value Thin Wafer Support Technology for 3DIC

2014 ◽  
Vol 2014 (1) ◽  
pp. 000718-000723
Author(s):  
Jared Pettit ◽  
Alman Law ◽  
Alex Brewer ◽  
John Moore
Keyword(s):  
Adhesion Force ◽  
Low Cost ◽  
New Technology ◽  
Value Added ◽  
Batch Process ◽  
New Approach ◽  
Wide Range ◽  
Temporary Bonding ◽  
Technical Challenges ◽  
Conventional Practice

As the 3DIC market matures, more is understood about the technical and cost challenges [1]. At the 2013 Semicon-West gathering, a panel of global experts identified these technical challenges to represent some of the most significant barriers to the industry's efforts to maintain progress with Moore's Law [2]. Searching and achieving high value manufacturing of 3DIC devices requires wrestling with several technologies and processes, all which may assert a different value for the manufacturer [3]. Current technologies for thin wafer support use a wide range of adhesives applied to the device wafer, bonded to a carrier, backside processed, and de-bonded by an array of methods. Daetec has been investigating temporary bonding for nearly 15yrs, is producing a range of products for semiconductor (e.g. WaferBondTM (Brewer-Science, Inc.)) [4], and for the display market using a low-cost tunable adhesion-force material that is peeled by simple means [5]. Daetec has developed a new technology, DaeBond 3DTM, allowing de-bonding to occur in a batch process while thinned wafers are affixed to film frames. This new approach provides a shift in conventional practice. Our paper presents several temporary bonding options with DaeBond 3DTM in an effort to define value-added approaches for thin wafer handling.

scholarly journals The adhesion model considering capillarity for gecko attachment system

2007 ◽  
Vol 5 (20) ◽  
pp. 319-327 ◽  
Author(s):  
Tae Wan Kim ◽  
Bharat Bhushan
Keyword(s):  
Capillary Force ◽  
Adhesion Force ◽  
Adhesive Force ◽  
Contact Angles ◽  
Adhesion Forces ◽  
Real Area Of Contact ◽  
Wide Range ◽  
Elliptical Integral ◽  
Gecko Adhesion ◽  
Surface Construction

Geckos make use of approximately a million microscale hairs (setae) that branch off into hundreds of nanoscale spatulae to cling to different smooth and rough surfaces and detach at will. This hierarchical surface construction gives the gecko the adaptability to create a large real area of contact with surfaces. It is known that van der Waals force is the primary mechanism used to adhere to surfaces, and capillary force is a secondary effect that can further increase adhesive force. To investigate the effects of capillarity on gecko adhesion, we considered the capillary force as well as the solid-to-solid interaction. The capillary force expressed in terms of elliptical integral is calculated by numerical method to cope with surfaces with a wide range of contact angles. The adhesion forces exerted by a single gecko spatula in contact with planes with different contact angles for various relative humidities are calculated, and the contributions of capillary force to total adhesion force are evaluated. The simulation results are compared with experimental data. Finally, using the three-level hierarchical model recently developed to simulate a gecko seta contacting with random rough surface, the effect of the relative humidity and the hydrophobicity of surface on the gecko adhesion is investigated.

Bovine Serum Albumin Adhesion Force Measurements Using an Atomic Force Microscopy

2008 ◽  
Vol 32 ◽  
pp. 49-52 ◽  
Author(s):  
Chun Chih Lai ◽  
John M. Bell ◽  
Nunzio Motta
Keyword(s):  
Atomic Force Microscopy ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Adhesion Force ◽  
Direct Method ◽  
Substrate Surface ◽  
Liquid Environment ◽  
Force Microscopy ◽  
Atomic Force

A new, direct method has been developed to measure the adhesion forces of bovine serum albumin (BSA) on surfaces by using Atomic Force Microscopy (AFM) in liquid environment. We were able to measure interactions between proteins and substrate surface in PBS solution directly without any modification to the substrate or the AFM tip. Two different surfaces have been used in the experiments: mica (hydrophilic surface) and polystyrene (hydrophobic surface). The results show that a polystyrene surface is more adhesive to BSA than a mica surface. This is consistent with previous research, which assessed that hydrophobic surfaces enhance protein adhesion but hydrophilic surfaces do not, demonstrating the effectiveness of the technique.

Crack Reduction in Tabbing and Stringing Processes for Solar Cells

2018 ◽  
Vol 777 ◽  
pp. 126-131 ◽  
Author(s):  
Atcharapha Kongwiriyaphaisan ◽  
Viboon Tangwarodomnukun
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Adhesion Force ◽  
Substrate Surface ◽  
Production Yield ◽  
Silicon Solar Cells ◽  
Mechanical Loads ◽  
Soldering Temperature ◽  
Soldering Time ◽  
Cell Manufacturing

Wafer cracking is considered to be an important loss in solar cell manufacturing as it crucially affects the production yield as well as the efficiency of solar cells fabricated. There is a certain chance of cracking in wafer when the substrate undergoes some thermal and/or mechanical loads during its fabrication. This research therefore aims to decrease the solar cells cracking in tabbing and stringing processes as the two processes are responsible for a great number of cracks in the substrate. A set of experiments was performed in this study, where soldering temperature and time were tested and the amount of cracks in solar cells was quantified. The findings showed that the use of 185°C soldering temperature with the soldering time of 1,200 ms can reduce the number of cracks in the tabbing and stringing of silicon solar cells. With this setup, the adhesion force between tabbing ribbons and substrate surface can also be promoted, thus preventing the delamination problem in the cell panels.

Aqueous Washable Thermal Resistant Coatings and Adhesives

2018 ◽  
Vol 2018 (1) ◽  
pp. 000767-000772 ◽  
Author(s):  
John Moore
Keyword(s):  
Laser Processing ◽  
Protective Coatings ◽  
Water Film ◽  
Water Soluble ◽  
Major Constituent ◽  
Organic Substrates ◽  
Uv Curable ◽  
Porous Carriers ◽  
Temporary Bonding ◽  
Industry Needs

Abstract Many packaging processes require thin and fragile components to be protected or held securely in place for temporary periods of time. The most common process flow is to: apply the coating, cure or use to bond a device, conduct the process, and finish with removing the coating by washing in a liquid chemistry. Aqueous cleaning is deemed safer for devices on organic laminates and in the presence of molding compounds. These reagents use water as their major constituent. They are compatible with organic substrates (panels, laminates, boards), are worker safe, and require less expensive operating equipment. Aqueous washing is generally green and exempt from the complexity and cost of environmental and waste management regulations. Daetec's washable coatings qualify as green, and exhibit thermal resistance over 300°C, making them one of the most unique materials on the market. These coatings enable soldering, laser processing, plasma etching, and dielectric curing, all following with simple water washing. Water washable DaeCoatTM 525 is a key choice in laser processing for debris removal around the heat activation zone (HAZ), while the etch-resistant DaeCoatTM 534 supports laser patterning for plasma singulation [1]. While DaeCoatTM 532 is water soluble, another material from the same family, DaeCoatTM 537 is not, yet will wash away in an aqueous surfactant, DaeClean™ S20 (10% in water). In many ways, these products act, as surfactants, but depending upon the chemistry, will dissolve in water or an aqueous agent. Customers desiring a green protective coating or adhesive for plating or etching processes, may apply DaeCoatTM 537, send through the processes, and then wash away in the S20 aqueous agent. All products are cast from water. Film forms as 50μm thick with peel away liners are available for DaeCoatTM 532 and 537. UV curable high solids versions are also available. Applications include planarizing coatings, adhesive for die solder attach, and C4 or micro bump protection. Protective coatings for EMI/RFI shielding, dicing operations, and temporary bonding operations that may use porous carriers have been demonstrated with water washable coatings and adhesives. The success in these and related temporary applications depend upon the use of the proper washable coating. Our experience in creating solutions for these and other industry needs will be discussed as well as the criteria for using temporary washable coatings.

scholarly journals Running-in behavior of a H-DLC/Al2O3 pair at the nanoscale

Friction ◽  
2020 ◽  
Author(s):  
Pengfei Shi ◽  
Junhui Sun ◽  
Yunhai Liu ◽  
Bin Zhang ◽  
Junyan Zhang ◽  
...  
Keyword(s):  
Adhesion Force ◽  
Substrate Surface ◽  
Friction Reduction ◽  
Van Der Waals Interactions ◽  
Strong Hydrogen Bond ◽  
Asperity Contact ◽  
Layer Formation ◽  
Transfer Layer ◽  
Dlc Film ◽  
Hydrogen Bond Interactions

AbstractDiamond-like carbon (DLC) film has been developed as an extremely effective lubricant to reduce energy dissipation; however, most films should undergo running-in to achieve a super-low friction state. In this study, the running-in behaviors of an H-DLC/Al2O3 pair were investigated through a controllable single-asperity contact study using an atomic force microscope. This study presents direct evidence that illustrates the role of transfer layer formation and oxide layer removal in the friction reduction during running-in. After 200 sliding cycles, a thin transfer layer was formed on the Al2O3 tip. Compared with a clean tip, this modified tip showed a significantly lower adhesion force and friction force on the original H-DLC film, which confirmed the contribution of the transfer layer formation in the friction reduction during running-in. It was also found that the friction coefficient of the H-DLC/Al2O3 pair decreased linearly as the oxygen concentration of the H-DLC substrate surface decreased. This phenomenon can be explained by a change in the contact surface from an oxygen termination with strong hydrogen bond interactions to a hydrogen termination with weak van der Waals interactions. These results provide new insights that quantitatively reveal the running-in mechanism at the nanoscale, which may help with the design optimization of DLC films for different environmental applications.

scholarly journals Evidence for intermolecular forces involved in ladybird beetle tarsal setae adhesion

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Naoe Hosoda ◽  
Mari Nakamoto ◽  
Tadatomo Suga ◽  
Stanislav N. Gorb
Keyword(s):  
Free Energy ◽  
Surface Free Energy ◽  
Adhesion Force ◽  
Intermolecular Forces ◽  
Adhesive Force ◽  
Work Of Adhesion ◽  
Polar Component ◽  
Adhesion Mechanism ◽  
Ladybird Beetle ◽  
Ladybird Beetles

AbstractWhy can beetles such as the ladybird beetle Coccinella septempunctata walk vertically or upside-down on a smooth glass plane? Intermolecular and/or capillary forces mediated by a secretion fluid on the hairy footpads have commonly been considered the predominant adhesion mechanism. However, the main contribution of physical phenomena to the resulting overall adhesive force has yet to be experimentally proved, because it is difficult to quantitatively analyse the pad secretion which directly affects the adhesion mechanism. We observed beetle secretion fluid by using inverted optical microscopy and cryo-scanning electron microscopy, which showed the fluid secretion layer and revealed that the contact fluid layer between the footpad and substrate was less than 10–20 nm thick, thus indicating the possibility of contribution of intermolecular forces. If intermolecular force is the main physical phenomenon of adhesion, the force will be proportional to the work of adhesion, which can be described by the sum of the square roots of dispersive and polar parts of surface free energy. We measured adhesion forces of ladybird beetle footpads to flat, smooth substrates with known surface free energies. The adhesive force was proportional to the square-root of the dispersive component of the substrate surface free energy and was not affected by the polar component. Therefore, intermolecular forces are the main adhesive component of the overall adhesion force of the ladybird beetle. The footpads adhere more strongly to surfaces with higher dispersive components, such as wax-covered plant leaves found in the natural habitat of ladybird beetles. Based on the present findings, we assume ladybird beetles have developed this improved performance as an adaptation to the variety of plant species in its habitat.

scholarly journals The initial run-in and long-term drift of the adhesive force between polycrystalline silicon MEMS sidewalls

2021 ◽  
Author(s):  
Jaap Kokorian ◽  
W. Merlijn van Spengen
Keyword(s):  
Polycrystalline Silicon ◽  
Adhesion Force ◽  
Adhesive Force ◽  
Adhesion Forces ◽  
Useful Knowledge ◽  
Optical Displacement ◽  
Short Run ◽  
Force Resolution ◽  
Region Ii

AbstractIn this paper we measure the evolution of adhesion between two polycrystalline silicon sidewalls of a microelectromechanical adhesion sensor during three million contact cycles. We execute a series of AFM-like contact force measurements with comparable force resolution, but using real MEMS multi-asperity sidewall contacts mimicking conditions in real devices. Adhesion forces are measured with a very high sub-nanonewton resolution using a recently developed optical displacement measurement method. Measurements are performed under well-defined, but different, low relative humidity conditions. We found three regimes in the evolution of the adhesion force. (I) Initial run-in with a large of cycle-to-cycle variability, (II) Stability with low variability, and (III) device-dependent long term drift. The results obtained demonstrate that although a short run-in measurement shows stabilization, this is no guarantee for long-term stable behavior. Devices performing similarly in region II, can drift very differently afterwards. The adhesion force drift during millions of cycles is comparable in magnitude to the adhesion force drift during initial run-in. The boundaries of the drifting adhesion forces are reasonably well described by an empirical model based on random walk statistics. This is useful knowledge when designing polycrystalline silicon MEMS with contacting surfaces.

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