Surface Mount Research Articles

Combination of Ceramic Laser Micromachining and Printed Technology as a Way for Rapid Prototyping Semiconductor Gas Sensors.

The work describes a fast and flexible micro/nano fabrication and manufacturing method for ceramic Micro-electromechanical systems (MEMS)sensors. Rapid prototyping techniques are demonstrated for metal oxide sensor fabrication in the form of a complete MEMS device, which could be used as a compact miniaturized surface mount devices package. Ceramic MEMS were fabricated by the laser micromilling of already pre-sintered monolithic materials. It has been demonstrated that it is possible to deposit metallization and sensor films by thick-film and thin-film methods on the manufactured ceramic product. The results of functional tests of such manufactured sensors are presented, demonstrating their full suitability for gas sensing application and indicating that the obtained parameters are at a level comparable to those of industrial produced sensors. Results of design and optimization principles of applied methods for micro- and nanosystems are discussed with regard to future, wider application in semiconductor gas sensors prototyping.

Model predictive control of direct-driven surface-mounted permanent magnet synchronous generator based on active disturbance rejection controller

PurposeThis paper aims to mainly discuss how to suppress the disturbances accurately and effectively in the wind energy conversion system (WECS) of the direct drive surface mount permanent magnet synchronous generator (SPMSG).Design/methodology/approachThe disturbances in wind energy conversion system have seriously negative influence on the maximum power tracking performance. Therefore, a model predictive control (MPC) method of model compensation active disturbance rejection control (ADRC) strategy in parallel connection is designed, which optimizes the speed tracking performance compared with the existing control strategy of MPC and ADRC in series connection. Based on the traditional ADRC, a multi parameter model compensation ADRC strategy is added to better estimate the disturbances. At the same time, a torque feedback strategy is added to compensate the disturbances caused by load torque and further optimize the speed loop tracking performance.FindingsThe simulation results show that the designed control method has advantages than the traditional control method in compensating the disturbances and tracking the maximum power more effectively.Originality/valueThe simulation results show that the designed control method is superior to the traditional proportional control method, which can better compensate the internal and external disturbances and track the maximum power more effectively.

Design and Performance of Additively Manufactured In-Circuit Board Planar Capacitors

This article discusses the design and performance of planar capacitors built as pairs of conductive plates by additive manufacturing as part of an electronic circuit board. This article covers several geometries and layers of parallel plates that allow for different capacitance values, from a few picofarads (pF) to several nanofarads (nF). The dc, ac, and radio frequency (RF) characterization demonstrated superior performance compared to off-the-shelve surface mount device (SMD) capacitors up to 20 GHz. The additively manufactured capacitors exhibit breakdown voltages in excess of 1 kV and subpicoampere leakage currents, while the change in RF impedance changes, as a function of frequency, is a factor of $3\times $ smaller than SMD capacitors.

Quality control in cyber-physical systems of smart electronics manufacturing

The creation of high-tech smart industries is observed in dynamically developing industries, which include the production of electronics and the automotive industry. The concept of “smart manufacturing” is closely related to the concept of cyber-physical systems, which integrates the main elements of digitalization and intellectualization. This concept provides for the continuous improvement of intellectual “cybernetic” resources for the effective management of the “physical” environment considered in this problem area. Improvement of technologies, ensuring high rates of reproducibility and suitability of equipment creates conditions for defect-free production. However, there remain the problems of recognizing patterns represented not by an obvious marriage, but by some not fully defined inconsistency on a set of requirements. The need to disclose uncertainties of this kind is typical for surface mounting technologies for printed circuit boards. The introduction of more and more advanced automatic optical inspections, containing the possibility of introducing intelligent (cybernetic) means, creates conditions for improving the quality of printed circuit boards as a “physical” environment. It is also important to minimize the “human factor”, the presence of which is still used when making decisions on the results of control. In the article, ensuring the rhythm of digital production and increasing the reliability of control in quality management in smart high-tech industries using the example of electronics production.

A low-cost development of automatic weather station based on Arduino for monitoring precipitable water vapor

Water vapor is the engine of the weather system. Continuous monitoring of its variability on spatial and temporal scales is essential to help improve weather forecasts. This research aims to develop an automatic weather station at low cost using an Arduino microcontroller to monitor precipitable water vapor (PWV) on a micro-scale. The surface meteorological data measured from the BME280 sensor is used to determine the PWV. Our low-cost systems also consisted of a DS3231 real-time clock (RTC) module, a 16×2 liquid crystal display (LCD) module with an I<sup>2</sup>C, and a micro-secure digital (micro-SD) card. The core of the system employed the Arduino Uno surface mount device (SMD) R3 board. The measurement results for long-term monitoring at the tested sites (ITNY and GUWO) found that the daily mean error of temperature and humidity values were 1.30% and 3.16%, respectively. While the error of air pressure and PWV were 0.092% and 2.61%, respectively. The PWV value is higher when the sun is very active or during a thunderstorm. The developed weather system is also capable of measuring altitude on pressure measurements and automatically stores daily data. With a total cost below 50 dollars, all major and support systems developed are fully functional and stable for long-term measurements.

Waveguide Cell With Water Filling for Passive Intermodulation Localization on Planar Circuits

This work presents a novel miniaturized waveguide cell with water filling for passive intermodulation (PIM) localization on planar circuits. The planar circuit as printed circuit board (PCB) is excited in a small waveguide, while its PIM product is detected simultaneously. The waveguide width is minimized by water filling (high permittivity dielectric), and the localization resolution is enhanced. During test, the PCB only needs move through the waveguide twice, once along its <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$X$ </tex-math></inline-formula> -direction and once along its <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Y$ </tex-math></inline-formula> -direction. By crossing the peak PIM distribution line along two directions together, the regions on PCB have PIM responses that can be decided. The proposed method is intended for the planer PCB and other normal PCB with surface mount components.

Factors Controlling the Defect Formation in Cu-Sn Micro Joints in 2.5D and 3D Interconnects

The Cu-Sn reaction upon soldering has been thoroughly studied and the sporadic formation of Kirkendall voids within the intermetallic bonds between ball grid array (BGA) or surface mount technology (SMT) solder joints and Cu pads has been demonstrated as well-known concern. However, in the realm of ever developing device miniaturization, there is very limited information on the impact of space confinement on the dynamics of the Cu/solder joint interface. It is known that no voiding has been found in solder joints with high-purity Cu but this phenomenon presents itself, albeit to a different extent, when the joint is realized with electroplated Cu. Also, it is believed, that the voiding propensity in the Cu3Sn intermetallic compounds (IMC) is more likely to be higher in micro joints than in BGA/CSP scale (macro) joints for a given quality of electroplated Cu. Along with that it has been shown that the IMCs on Cu surfaces seem to grow much faster when the solder becomes very thin, and this is accompanied with a greatly enhanced risk of Kirkendall void nucleation.The emphasis of this work is on understanding the voiding behavior within the intermetallic bonds of Cu-Sn micro joints (5 – 30 µm) with the eventual goal of learning how it can be controlled or prevented. Our systematic studies have corroborated the association of voiding with the incorporation of small concentrations of impurities resulting from organic additives degradation during the Cu electroplating as already illustrated for macro joints. Our results also show lack of any voiding not only in macro- but also in micro joints when the interconnection is realized with high purity Cu, likely because no organic impurities are present in sufficient amount to prompt defect nucleation and growth. Our research further demonstrates that the IMC growth rate varies with factors and parameters such as solder volume to pad area ratio, solder composition, pad finish, initial assembly process parameters, subsequent heat treatments, and specifics of the further thermomechanical history, thus impacting differently the overall voiding level. Following this lead, the analysis of micro joints subjected to different synthetic and processing treatments clearly demonstrates the propensity for voiding to be substantially higher, for a given quality of electroplated Cu, in very small solder joints (5 – 30 µm), such as those found in 3D assemblies, unlike in macro joint counterparts. The risk and severity of voiding in these thinner joints is confirmed to depend on the type and amount of incorporated organic impurities in the electroplated Cu. Therefore, in the present report we show how the bath additive chemistry and various Cu electroplating parameters play a systematic role in the type and quantity of impurity incorporation, and thus the propensity for voiding. Approaches to control the electroplating Cu quality in a way that leads eventually to void-free micro joints are also discussed.

Constraining Emission Estimates of CFC-11 in Eastern China Based on Local Observations at Surface Stations and Mount Tai

Constraining Emission Estimates of CFC-11 in Eastern China Based on Local Observations at Surface Stations and Mount Tai

Directional microwave coupled-line couplers with high lateral coupling level

Classic сoupled-line couplers with a high lateral coupling level by type of directivity are counterdirectional. Restrictions on their synthesis are imposed by the gap between transmission lines, which must be extremely small (tens of microns), the difference in the phase velocities of even and odd modes, which must be compensated and others. This makes it difficult of manufacturing couplers. Described in technical literature сoupled-line couplers with a high lateral coupling level with changed types of directivity are either quite bulky or have small dimensions due to the use of discrete inductors and capacitances, which complicates the technological process with surface mounting when implementing the final device. In this article we propose a compact сoupledline coupler with a high lateral coupling level, which implements power transfer to a single port (0 dB, crossover). The coupler topology uses periodic loops that are located between сoupled-line. The equivalent circuit of the coupled lines was calculated and analyzed for a single periodic stub. This allowed us to determine the necessary parameters and dimensions of the topology. The device is narrow-band (3 GHz ± 5 %), transmission coefficient minus 0.44 dB at the center frequency of 3 GHz, isolation for isolated ports is not less than 35 dB. The proposed compact coupler with a coupling level of 0 dB suits building distribution circuits in which it is necessary to exclude the intersection of transmission lines. The information on the synthesis of the 3 dB co-directional microwave coupler on coupled strip lines with lateral electromagnetic coupling is given. The coupler is characterized by a high isolation level with an isolated port, not less than 40 dB. The imbalance of the amplitudes between the working (through and connected) and the input port is minus (3.4 ± 0.8) dB.

Efficient and Low-Cost PD Monitoring and Locating System for MV Switchgears Using TEV Detectors

Identifying the location of partial discharges (PDs) and providing clear information on insulation vulnerabilities in power systems can help utility companies to improve their maintenance efficiency. This paper presents a PD monitoring and locating system for medium-voltage switchgears using a set of transient earth voltage (TEV) detectors. A time-of-flight methodology was used to identify the switchgear affected by PD among a row of switchgears. A time sharing access mechanism, which was implemented by multiple high-frequency surface mounting relays integrated into each TEV detector, was applied to automatically identify the site of PD and minimize the number of expensive high-speed acquisition cards. The operation principle and implementation of the modular system were formulated, and the efficiency of the proposed system in identifying the switchgear with PD among three 10 kV metal-clad switchgears was confirmed experimentally.

Surface mounted devices classification using a mixture network of DCNN and DFCN

In tradition, surface mounted devices (SMD) are classified and registered manually in surface mount technology (SMT). Manual classification is inefficient and relies on the experience of the operators. We propose a novel SMD classification method based on a mixture neural network. The network contains two modules, one is a convolutional neural network with a gray image as input, and the other is a fully connected network with a Hand-Crafted feature as input. The lighting environment of chip has a great impact on chip imaging, and the classification method should maintain sufficient robustness against light changes in SMT. However, there is a lack of a robust feature extraction method for SMT classification against illumination changes. A novel feature extraction method based the characteristics of the binary chip image is first proposed, which is composed of the mathematical statistical pin parameters of SMD. As the light changes, the binary image is relatively stable, making the proposed feature is invariant to light changes. An SMD dataset in SMT contains 61 kinds of chips is built for training and testing. Experiments on this dataset demonstrate that our method is more effective than the state-of-the-art methods in terms of performance measures.

Design and Fabrication of Piezoelectric Artificial Cilia for Airflow Sensing in Mobile Robot with Surface Mount

In order to realize the measurement of airflow velocity in narrow spaces, we fabricate, package and characterize a flexible and surface mount piezoelectric artificial cilia (PAC) for airflow sensing in a piezoelectric mobile robot (PMR). The diameter and height of the cilia are 0.3 mm and 5 mm, respectively, whose sensitivity is 30 (mV)/(m/s). Meanwhile, the PMR is 32.8 g in mass and 55 mm × 50 mm × 20 mm in size and it is capable of achieving a velocity of 200 mm/s. This sensing robot has advantages of light weight, miniature size, and low cost, which has potential to effectively evaluate air leakage in the pipeline.

Evaluation of detatchable board-to-board interconnects on screen printed electronic structures

Hybrid printed electronics (HPE) combines advantages of conventional electronics manufacturing technologies such as surface mount technology with those of printed electronics in order to realize more complex electronic systems. To realize the final product, such HPE subassemblies have to be connected to higher-level assemblies. So far interconnection techniques for the so-called level 3 interconnection between printed subsystems and standard electronics have not yet been considered adequately in scientific research. In this paper, alternative detachable level 3 interconnection technologies, i.e. spring loaded contact pins, zero insertion force (ZIF) as well as Non-ZIF connectors are investigated systematically regarding their electrical behaviour against the background of printed electronics. Screen-printed silver filled polymer thick film paste is used to realize printed conductor patterns on flexible polymer substrates, which are connected later on with the alternatives mentioned above. Transition resistance is measured using the four wire method as produced, after repeated mating cycles as well as after accelerated aging tests. The various electrical contacts are subjected to thermal stress in temperature cycling testing and during aging at a constant high temperature. As a result it can be stated, that the sping-loaded contact pins used in this investigation show superior behavior compared with the selected connectors in terms of resistance increase after mating cycles. Concerning long-term behavior after thermal cyling and high temperature storage, all investigated alternaives reveal convincing results.

Research on Furnace Temperature Curve Based on Linear Regression Model

With the rapid development of social science and technology, various industries have higher and higher requirements for the quality of electronic products. SMT surface mount technology is the most popular process in the electronics assembly industry, and reflow soldering is one of the SMT mounting processes. Reflow soldering is mainly used to solder the circuit boards with components already attached. The solder paste is melted by heating to fuse the chip components and the circuit board pads together, and then the solder paste is cooled by the cooling of the reflow soldering, and the components are soldered. The plates are solidified together, and the furnace temperature curve records the temperature changes of the circuit board during this process. This article focuses on the printed circuit board welding production problem, through optimizing the furnace temperature curve for high-efficiency and quality-guaranteed production, and researches on the changes of the furnace temperature curve at different temperatures.

The Impact of Using Portable Sealer on Drop Out Component' Number at Surface Mounting Technology Production Line

The study aims to reduce the drop out of components that occur in the surface-mounting technology production line of PT. TEC Indonesia. This effort is carried out by designing a portable sealer product to glue the cover tape and carrier tape component products made in the line. In order to obtain the best value indicator for product design, this study uses a quantitative factorial design technique to determine value reduce drop out of components in the surface mounting technology (SMT) production of the parameter combination use of adhesive strength produced by the product. Information on study data obtained through the concept of experimental design (DOE) using temperature and treatment time parameters resulting from the product's design. Results of the tests have been carried out. Information on the adhesive strength reaches standard is rated at a temperature 1200 C for one two and three seconds, which can produce adhesion of 0.029 Kgf (the standard value is at 0.02-0.07 Kgf). In addition, the number of drop-out components produced after using the product has decreased significantly to zero, which previously reached an average of two to three components that were damaged or defective (test data).

Design and implementation of a dual band bioinspired leaf rectenna for RF energy harvesting applications

In this article, both design and implementation of a novel Omni-directional bioinspired Linden leaf-shaped rectenna are reported. The antenna is designed for the energy harvesting purposes under the operation frequency range between 1.6 and 2.65 GHz with a second harmonic rejection property. At the rectifier stage, voltage doubler circuit is designed and implemented with the help of microstrip transmission lines, which are used for impedance matching procedure between the antenna and the rectifier for the optimum power transfer from the antenna to the load for the operation dual bands of universal mobile telecommunication service and WIFI. In the design, SMS7630Schottky diodes, high frequency capacitors and inductors are used as the main surface mount devices. The FR4 epoxy material is selected as a substrate material for both the antenna and the rectifier circuit due to its low cost and easy—production scheme. The maximum efficiency value realized at the dual band operation is 42% at the 0 dBm input power level. The output voltage value and the harvested power at this point are nearly 960 mV and 0.42 mW with an optimum load RL = 2.2 KOhm. The implemented system can be used efficiently for the RF energy harvesting applications for the proposed frequency bands.

Assessing product quality from the production process logs

A real challenge for manufacturing industry is to be able to control not only the manufacturing process but also the production quality. Products that are suspected to be faulty are deviated from their nominal path in the production line and inspected more closely. The fact that some products deviate from the nominal path and others fail at some check operations can be used as an indicator of poor product quality. Based on this idea, this paper proposes a method to compute a product quality index or more exactly a penalty index taking into account both product path and production batches. The method relies on categorizing the products according to how they follow the production path and process mining techniques. The originality of the proposed index is to be built from advanced data analysis techniques enhanced by expert know-how. The quality index highlights risk of customer return, which is highly relevant information for the after sales service. The significance of the method is illustrated on a printed circuit board production line using surface mount technology at Vitesco Technologies. Data is collected from the real manufacturing execution system. The results obtained over more than 10,000 single electronic boards show that 91.7% of the products are in good compliance with respect to the requirements. For the other products, the method identifies the root causes of poor quality that may call for maintenance or reconfiguration actions.

Defect patterns study of pick-and-place machine using automated optical inspection data

PurposeThis paper aims to study the component pick-and-place (P&P) defect patterns for different root causes based on automated optical inspection data and develop a root cause identification model using machine learning.Design/methodology/approachThis study conducts experiments to simulate the P&P machine errors including nozzle size and nozzle pick-up position. The component placement qualities with different errors are inspected. This study uses various machine learning methods to develop a root cause identification model based on the inspection result.FindingsThe experimental results revealed that the wrong nozzle size could increase the mean and the standard deviation of component placement offset and the probability of component drop during the transfer process. Moreover, nozzle pick-up position can affect the rotated component placement offset. These root causes of defects can be traced back using machine learning methods.Practical implicationsThis study provides operators in surface mount technology assembly lines to understand the P&P machine error symptoms. The developed model can trace back the root causes of defects automatically in real line production.Originality/valueThe findings are expected to lead the regular preventive maintenance to data-driven predictive and reactive maintenance.

Industrial Dataspace for smart manufacturing: connotation, key technologies, and framework

Smart manufacturing is a popular concept for smarter decision-making and more efficient production. Although distributed methods for data management and processing in smart manufacturing have many advantages such as low cost of adaptation and convenience for local database, some methods are hard to manage variable data sources and discover proper range of data for smart decision-making. Therefore, Dataspace is considered in this article to be a feasible and effective method. From the relation-defined perspective of utilisation of industrial Big Data, the contribution is a novel industrial Dataspace design with static structure and working flow paths for smart manufacturing. In design, the industrial Dataspace platform has been proposed to accommodate smart manufacturing characteristics with the intelligence of pay-as-you-go, like harnessing distributed heterogenous data from industrial enterprises, understanding industrial data by ontology or knowledge, corelating the data with smart applications, and enabling related decisions. A further analytical case in Surface Mounting Technology manufacturing of welding procedure is provided to illustrate the execution of customisation, focused and related decision support, and system evolution within industrial Dataspace.

In-mold lightweight integrating for structural/functional devices

Abstract Integration of function in structure is troublesome for structural/functional devices. A novel method of in-mold integrating for structural/functional devices was proposed and studied. In this method, a functional film was prepared by printing and surface mounting to achieve electrical functions, and then the film was formed and back molded into a final product. Owing to the complex electronic film, new problems are raised in the in-mold integrating process. The process was modeled, and was designed with the genetic algorithm. The interaction between the melt and the mounted film was analyzed by two-way fluid-structure coupling. Heat dissipation with anisotropic thermal conductivity was examined. Accordingly, a control panel was manufactured and tested. From the study, the functional film, causing asymmetrical cooling issue, results in concave warpage, which can be effectively controlled by comprehensive processing optimization. Film deformation is significant at button area because of tiny hollow structure. The deformation can be decreased by the epoxy encapsulation. The anisotropic thermal conductivity and injection layer cause heat dissipation problem, and thermal effect should be checked and designed by full thermal analysis. With the designed scheme, manufactured panels can perform all control functions, satisfy appearance requirements, and achieve lightweight performance.