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Liquid encapsulation techniques have been used extensively in advanced semiconductor packaging, including applications of underfilling, cavity‐filling, and glob top encapsulation. Because of the advanced encapsulation materials and the automatic liquid dispensing equipment involved, it is very important to understand the encapsulation material characteristics, equipment characteristics, encapsulation process development techniques in order to achieve the encapsulation quality and reliability. In this paper, the authors will examine the various considerations in liquid encapsulation applications and address the concerns on material characterization, automatic liquid dispensing equipment/process characterization and the encapsulation quality and reliability. The discussions will be helpful for future material and process development of semiconductor packages.

This study aims to encapsulate the crude carotene pigment isolated from waste portion of Cucurbita maxima with the help of different encapsulating agents through lyophilization to transform crude pigment into stable form for further utilization.

This paper opted for encapsulation of extracted carotene pigment by lyophilization using various carrier materials such as maltodextrin 20 dextrose equivalent (DE), maltodextrin 10 DE and tapioca starch along with emulsifier polysorbate-80. After encapsulation of crude carotene pigment, prepared encapsulated powder was subjected to chemical analysis. The data was analysed statistically by a complete randomized design.

Maximum encapsulation efficiency, carotene content, antioxidant activity and water solubility index were achieved when 0.06% of crude carotene pigment was emulsified with same quantity of polysorbate-80, followed by encapsulation with 20% of maltodextrin 20 DE during lyophilization.

Even though few researchers have worked on the encapsulation of colour pigments, no researcher has reported encapsulation of carotene pigment extracted from waste of C. maxima.

Flip chips were assembled on to ceramic boards using eutectic tin‐lead solder with underfill and with/without encapsulation for temperature cycling and high‐temperature‐high‐humidity tests. After 1.5 years of testing, the reliability performance of the flip chip on board (FCOB) assemblies was compared. All of the FCOB assemblies with underfill, but without encapsulation, survived 5,778 cycles of the temperature cycling test following 5,005 hours of the high‐temperature and high‐humidity test. The results show that encapsulation may not necessarily enhance the reliability of flip chip assemblies and might therefore be omitted.

The purpose of this paper is to encapsulate aqueous dispersions of nano‐scale CI Pigment Red 122 prepared through ball milling into UV‐curable resins, 1,6 hexanediol diacrylate (HDDA, monomer), and polyester acrylate (oligomer) using the mini‐emulsion technique.

The encapsulation of pigment is achieved by mixing a surfactant‐stabilised pigment dispersions and a monomer/oligomer mini‐emulsions and subjecting both to mini‐emulsification conditions. A film of encapsulated pigment mini‐emulsion is finally UV cured using water‐soluble initiator. Efficient encapsulation is proven by ultra‐centrifugal sedimentation, scanning electron microscopy and thermogravimetric analysis (TGA). The stability of pigment dispersions and also the encapsulation process are investigated.

TGA and ultracentrifuge sedimentation results showed that CI Pigment Red 122 is successfully encapsulated into polyester acrylate/HDDA resins. The oligomer (polyester acrylate) in the presence of organic pigment could stabilise the mini‐emulsion droplets without introducing any other hydrophobes (co‐stabiliser) in the formulation. In addition, the encapsulation percentage and suspension stability of mini‐emulsion are best when the polyester acrylate/HDDA weight ratio is 3:2.

The UV‐curable resins used in the present context are 1,6 HDDA and polyester acrylate. Besides, various oligomer/monomer composition types could be used and its impact on encapsulation efficiency could be also studied.

This method of encapsulation is practically effective for modification of organic pigments for use in UV‐curable ink‐jet printing inks.

The developed method is novel from a literature point of view and can be of a great benefit to achieve the required properties of pigmented UV‐curable system in inkjet printing of textiles. In addition, it could find numerous applications in surface coating.

The purpose of this paper is to evaluate the role of encapsulation temperature on the preparation of silica-encapsulated waterborne aluminium pigments.

The waterborne aluminium pigments were prepared with H₂O₂ as anchoring agent and siloxane used as precursors in pH = 9.0 medium at different temperatures. The anchorage and compactness of silicon which on aluminium surface were characterized by optical microscopy, scanning electron microscopy and N₂ adsorption-desorption. The anticorrosion property was characterized by the volume of produced hydrogen as a function of time.

The effect of encapsulation temperature on anticorrosion property of aluminium pigments is reflected from the anchorage and the compactness of silica on aluminium surface. Furthermore, when encapsulation temperature is 45-50°C, the silica platelets uniformly anchored on the aluminium surface as a dense film, which show the best anticorrosion property. Lower and higher encapsulation temperatures cause the silica platelets to agglomerate rather than anchor on the aluminium surface, which is unfavourable for the anchorage and the formation of compact silica film. The use of product in waterborne coatings gives a higher glossiness than that of raw material.

Only pH = 9.0 medium was explored, and the other pH medium could result in different optimum temperatures.

The investigation results provide theoretical basis for obtaining excellent waterborne aluminium pigments.

The method of investigating corrosion resistance mechanism of aluminium pigments based on anchorage and compactness is novel.

The purpose of this paper was to determine the influence of thermal aging on the stability of organic light-emitting diode (OLED) glass samples made in ambient condition.

The samples with yellow emitting layer (named as ADS5) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) hole transport layer were examined. Some of the devices were ultraviolet-curable epoxy encapsulation directly after performance. All samples were thermally annealed at 70°C for 1, 2, 3 and 4 hours. The characteristics current–voltage for fresh and aging samples in the range of voltage from 0-15 V were made. The temperature of OLEDs samples in real-time with a thermographic camera was measured too. Additionally, scanning electron microscope image of surface Al cathode immediately after OLED performance and after annealing tests was made.

The authors stated, that irrespective of the type, the samples were undergoing the degradation. The decrease in value of the current density was registered. That were about 44 per cent and about 24 per cent after thermally annealing the samples with and without encapsulation, respectively (at tension 13 V). Additionally, there were observed massive delamination of the metal cathode.

Influence of thermal annealing and encapsulation on the dynamic characteristics of the OLED devices fabricated in ambient condition was analyzed. There are not many papers in the literature describing examinations of OLED samples which were made in environmental conditions.

This paper discusses processes of flip chip on FR‐4 using eutectic solder bumps with possible fewer process steps compared to the full assembly process. Some interesting results in terms of the reliability performance of flip chip on FR‐4 assemblies using eutectic solder have been obtained after an almost‐one‐year temperature cycling test. The process steps of underfilling and curing of underfill can be omitted when a suitable epoxy is used for encapsulation. When underfill is conducted, encapsulation is not necessarily needed from a reliability point of view.

Virtual maintenance simulation is of great importance to help designers find and avoid design problems. During its simulation phase, besides the high precision requirement, collision detection must be suitable for all irregular objects in a virtual maintenance environment. Therefore, in this paper, a collision detection approach is proposed based on encapsulation for irregular objects in the virtual maintenance environment.

First, virtual maintenance simulation characteristics and several commonly used bounding boxes methods are analyzed, which motivates the application of encapsulation theory. Based on these, three different encapsulation methods are oriented to the needs of simulation, including encapsulation of rigid maintenance objects, flexible maintenance objects and maintenance personnel. In addition, to detecting collisions accurately, this paper divides the detection process into two stages. That is, in the first stage, a rough detection is carried out and then a tiny slice space is constructed to generate corresponding capsule groups, which will be redetected in the secondary stage. At last, several case studies are applied to illustrate the performance of the methodology.

The automatic construction algorithm for bounding boxes can be adapted to all forms of objects. The number of detection primitives are greatly reduced. It introduces the reachable space of the human body in maintainability as the collision search area.

The advantages of virtual maintenance simulation could also be advantageous in the industry with further studies. The paper believes this study is of particular interest to the readers of your journal.

The purpose of this study is to evaluate the role of encapsulation pH and iron source on the anchorage mode and performance of iron oxide-encapsulated aluminium pigments.

The coloured waterborne aluminium pigments were prepared at pH 5-7.5 by using FeSO₄ and FeCl₃ as iron source. The anchorage mode of iron oxides on aluminium was characterized using optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. Furthermore, the pigmentary performance was characterized through anticorrosion test and multi-angle spectroscopy.

Diaspore and boehmite could form from H₂O₂ oxidizing aluminium. Both low pH and FeSO₄ systems are beneficial for diaspore, inducing green rust anchor on the aluminium to form goethite. Either in FeSO₄ or FeCl₃ system, slightly high pH is beneficial for the formation of boehmite, which occurred together with ferrihydrite to form denser coating with yellowness and excellent anticorrosion property. At pH above 7, the formation of dendritic iron oxide is detrimental to the anticorrosion property and the glossiness.

Only FeSO₄·7H₂O and FeCl₃·6H₂O as iron sources were explored.

The investigation results provide theoretical basis to obtain excellent chromatic waterborne aluminium pigments.

The method for investigation of encapsulation mechanism by surveying the structure of iron oxides on aluminium, which varies with the pH of the system and iron sources, is novel.

This paper aims to present experimental and finite volume method (FVM)-based simulation studies on the scaling effect on the capillary contact angle and entrant pressure for a three-dimensional encapsulation process of ball-grid array (BGA).

With the development of various sizes of BGA packages, the scaling effect of BGA model on capillary underfill (CUF) process is investigated together with the influences of different industrial standard solder bump arrangements and dispensing methods used as case study.

The experimental results agree well to the simulation findings with minimal deviation in filling time and similar flow front profiles for all setups. The results revealed that the capillary contact angle of flow front decreases in scale-up model with larger gap height observed and lengthens the encapsulation process. Statistical correlation studies are conducted and accurate regression equations are obtained to relate the gap height to the completion filling time and contact angle. CUF threshold capillary pressures were computed based on Leverett-J function and found to be increasing with the scale size of the package.

These statistical data provide accurate insights into the impact of BGA’s scale sizes to the CUF process that will be benefiting the future design of BGA package. This study provided electronic designers with profound understanding on the scaling effect in CUF process of BGA, which may be extended to the future development of miniature-sized BGA and multi-stack device.

This study relates the flow behaviour of encapsulant to its capillary contact angle and Leverett-J pressure threshold, in the CUF process of different BGA and dispensing conditions. To date, no research has been found to predict the threshold pressure on the gap between the chip and substrate.