Cu-wire overhang bonding process is investigated first by a high-speed camera system. It was found that the greater impact, rebound, and deflection of overhang die during the Cu-wire bonding process happen since a hard Cu ball hits with the die with a 1.0-μm-thick Al pad, which affects the bonding strength. When the thickness of the Al pad on the die increases to 2.8 μm, its microhardness is three times lower than that of the 1.0-μm Al pad, which will help to improve the dynamics features of hard Cu overhang bonding. Real-time dynamics features prove that the loading process of the 2.8-μm-thick Al pad is much more stable than that of the 1.0-μm-thick Al pad. Furthermore, impact and rebound reduce significantly; thus, the shear strength of Cu-wire overhang bonding increases significantly.

Dynamics Features of Cu-Wire Bonding During Overhang Bonding Process

Due to the disadvantages of traditional mercury thermometers, such as longer measurement time and necessity of contact with the human body, a thermometer that uses infrared sensors to detect temperature without contact is designed. The Infrared temperature sensor MLX90614 is designed to collect human or object temperature by the SCM to process the temperature into the LCD display and alarm when over-temperature. Using software design to complete the control of the system. The smart thermometer can achieve non-contact measurement, place the thermometer in the forehead for a few seconds to get the body temperature, to alarm once the set value is exceeded. The design temperature range is 0-55 °C, and temperature resolution is 0.1 °C.

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Development of a Non-contact Infrared Thermometer

In view of the phenomenon of repeated development in data acquisition system, a universal data acquisition system was designed by using LabVIEW software based on NI-6358 data acquisition card Users could customize the conversion of each channel and store the configuration information through files A high-speed data acquisition and processing framework was proposed by combining state machine and production/consumer system, and it realized synchronous collection of 32 channels and display, convert, stored in real time The test and operation results showed that the system had high sampling rate, stable and reliable operation, and could meet the requirement of generality

Design of LabVIEW based general data acquisition system

Low-temperature microjoining, such as wire (or ribbon) bonding, tape automated bonding (TAB), and flip chip bonding (FCB), is necessary for electronics packaging. Each type of microjoining takes on various aspects but has common bonding mechanisms regarding friction slip, plastic deformation, and friction heating. In the present paper, solid-state microjoining mechanisms in Au wire (ball) bonding, FCB, Al wire bonding (WB), and Al ribbon bonding are discussed to systematically understand the common bonding mechanisms. Ultrasonic vibration enhances friction slip and plastic deformation, making it possible to rapidly obtain dry interconnects. Metallic adhesion at the central area of the bonding interface is mainly produced by the friction slip. On the other hand, the folding of the lateral side surfaces of the Au bump, Au ball, and Al wire is very important for increasing the bonded area. The central and peripheral adhesions are achieved by a slip-and-fold mechanism. The solid-state microjoining mechanisms of WB and FCB are discussed based on experimental results. [DOI: 10.1115/1.4038143]

Solid-State Microjoining Mechanisms of Wire Bonding and Flip Chip Bonding

In mechanical fault diagnosis of the high voltage circuit breakers (HVCBs), it is often expected that the fault type should be confirmed in time to avoid delaying the best time for mechanical fault diagnosis. The traditional diagnosis method of HVBC is not so profound for the identification of slight faults and does not consider the impact of the recall rate of fault samples on the fault diagnosis results. In this paper, we propose a method for HVCBs mechanical fault diagnosis utilizing variational mode decomposition (VMD) based on improved time segment energy entropy (ITSEE) and a new hybrid classifier. Firstly, the signal is decomposed into $K$ intrinsic mode functions (IMFs) via VMD to establish a component matrix. Secondly, the ITSEE method is used to calculate the energy entropy of the matrix in time domain and frequency domain, so as to better extract the features of slight fault types. Finally, an optimal hybrid classifier model combined of one-class support vector machine (OCSVM) and probabilistic neural network (PNN) is used to identify four types of vibration signals of HVCBs. The experimental results show that the accuracy of unknown samples is 98.75%, and the recall of fault type is 100%. The experimental results show the effectiveness of the method and have important application value for the diagnosis of HVBCs.

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Mechanical Fault Diagnosis of High Voltage Circuit Breakers Utilizing VMD Based on Improved Time Segment Energy Entropy and a New Hybrid Classifier

Based on LabVIEW, this paper presents a design scheme of data acquisition, which it proposes using computer and ordinary data collection card as the main hardware and LabVIEW as software development platform, thus constructs the virtual instrument system for signal acquisition. The system can realize synchronous data acquisition of single channel or multi-channel signal, as well as real-time display and preservation. The practice shows that this scheme can not only effectively play performance of ordinary data acquisition card, but also reduce greatly program development time and beautify interface through LabVIEW which has powerfully visual human-machine interface editor and graphical programming function.

Design of Data Acquisition System Based on LabVIEW

Investigation of the characteristics of overhang bonding for 3-D stacked dies in microelectronics packaging

According to Dynamic Link Library (DLL), the common motion card was successfully run on Labview virtual platform, which can graphically compile program. Based on Labview8.6 platform, Leadtech SMC-6480 control card and Yaskawa SJME-02AMA41 servo motor were used as the hardware to realize multi-axes motion control. The results indicated that each axis has three motion models of automatic, manual and return-to-zero, which can switch mutually at any time.

Research of Multi-Axes Motion Control System Based on LabVIEW Platform

Abstract The spindle system is important in the machine tool. The vibration signal generated by the spindle system in the machine tool has a great influence on the machining accuracy of the product and the abrasion and lifetime of the tool. Therefore, it is necessary to monitor the vibration signal in the machining process of the machine tool spindle in real time. The vibration sensor is used to monitor the vibration signal of the machine tool spindle in this paper. The data collected by the sensors are transmitted to the Bluetooth module by the serial port for wireless communication. The vibration signal and its frequency domain transformation of the spindle are received by LabVIEW software platform, and the original waveform is displayed, the threshold alarm and the storage of data are realized. The experimental results show that the designed system can realize the online monitoring of the vibration state of the machine tool spindle effectively.

Ling Gang Liu

Papers

Design of Data Acquisition System Based on LabVIEW

Investigation of the characteristics of overhang bonding for 3-D stacked dies in microelectronics packaging

Research of Multi-Axes Motion Control System Based on LabVIEW Platform

Machine tool spindle vibration monitoring system based on Bluetooth wireless network and LabVIEW