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With the development of advanced IC packaging technology, wafers are required to become thinner and thinner. The 12-inch memory wafer has reached within 25um, which requires a higher-performance aerostatic spindle of the wafer grinder. The spindle motor power of the wafer grinder is large, which generates a lot of heat. The heat causes the temperature rise of the aerostatic spindle, which adversely affects the wafer grinding accuracy and the reliability of the spindle motor operation. In this paper, the field-circuit coupling model of the spindle motor in the aerostatic spindle is established. The transient two-dimensional electromagnetic field is analyzed, and the no-load and load characteristics of the motor are obtained, which provides theoretical support for the design of the spindle motor. Using motor loss as the heat source, through the one-way coupling of electromagnetic field and temperature field, establish an aerostatic spindle thermal analysis model, and the steady-state temperature field of the aerostatic spindle and the rotating shaft is simulated and analyzed, and the temperature distribution of the aerostatic spindle and the rotating shaft is obtained, and the thermal deformation is analyzed. This paper has certain reference value for the optimization design of aerostatic spindle.

The gas spindle is a key component in wafer thinning equipment. The performance of the gas spindle directly affects the wafer processing quality. By establishing the mathematical model of the gas spindle thrust bearing flow field, the gas flow process in the orifice and gas film is studied, and the bearing capacity distribution of the thrust bearing is obtained. The variation of the bearing characteristics of the thrust bearing with the thickness of the gas film is analyzed in detail. Between 1μm ~ 11μm, the bearing capacity declines gently, and the capacity changes by only 2%. Between 12μm and 30μm, the bearing capacity has a significant downward trend, from 6800N to 1800N, a decrease of 73%. After 31μm, the change in bearing capacity is attributed to a gradual change. Before 18μm, the stiffness value increases with the increase of the thickness of the gas film, and increases rapidly. The maximum stiffness value appears at 18μm, which is 376N/μm. In addition, compared with the increasing trend of stiffness value, the downward trend is relatively gentle. Through the above research, it provides a theoretical reference for the development of thinning equipment.

In the point-to-point high-speed positioning process of the IC packaging mechanism, the nonlinear characteristics of the servo system influence the performance of the servo system to a different extent, which may easily cause resonance of the system and reduce die attach efficiency of the packaging equipment. Based on the above problems, this paper proposes a cross-global artificial bee PID algorithm to suppress mechanical resonance at the load end. Firstly, the reasons of resonance formation and the influence on the servo system are analyzed. Secondly, the modal of the swing arm mechanism in the IC packaging mechanism is analyzed. Finally, the experimental platform is built. The results show that the resonance of the load end is effectively controlled and the positioning efficiency is improved by 9.1%.

The flip chip package is an advanced chip interconnection technology, which has become a main technology of high density package. This paper mainly studies the influence of bumps deformation in the flip chip bonding process on connection reliability, which provides theoretical reference for the flip bonding process. Bumps deformation is a key factor for the chip reliable connection in the flip chip bonding. Bonding force directly determines the bumps deformation. The quality of the bumps will affect the reliability of reflow soldering and under-fill processes. This paper builds a three-dimensional model of flip chip bonding. By the FEM simulation analysis, the relationship between bonding force and bumps deformation is studied. The process parameters are optimized by comparing the experimental data with simulation result. Finally, the reliability evaluation method of flip chip bonding is obtained, which can be used to guide the research and development of the bonding equipment.

The light extraction has an important effect on LED encapsulation to obtain a high efficiency. The influence of packaging structure on LED light extraction was investigated in TracePro. Four kinds of high-power LED packaging methods based on the structure and the character of flip chip were presented, flip chip on board (1 reflective-cup), flip chip to substrate (1 reflective-cup), flip chip on board (100 reflective-cups) and flip chip to substrate (100 reflective-cups). Flip chip on board was that the LED chip was directly bonded to the aluminum substrate, flip chip to substrate was the LED chip bonded to the Si-Substrate before bonded to the aluminum. Two different structures of aluminum substrate were analyzed, 1 substrate with only 1 reflective cup and 1 substrate with 100 reflective cups. The final result shows that the luminous efficiency of flip chip on board (100 reflective-cups) is 0.03% higher than flip chip to substrate (100 reflective-cups); luminous efficiency of flip chip on board (1 reflective-cup1) is 0.04% lower than flip chip to substrate(1 reflective-cup). Luminous efficiency of flip chip on board (100 reflective-cups) is 10% higher than flip chip on board(1 reflective-cups); luminous efficiency of flip chip to substrate (100 reflective-cups) is 6.3% higher than flip chip to substrate(1 reflective-cup).

Wafer transferring process is often used in the semiconductor packaging equipment. Wafer transferring system is an essential part in the IC equipment. Smooth and efficiency are the design requirement of wafer transferring. As the rising of smart phones and tablet PCs, thin wafer is increasingly demanding. Large and thin wafer is susceptible to damage because of gravity during transmission, which greatly affect the efficiency and reliability of IC package. To get small deformation of the wafer, this paper analyzes the material parameters of the wafer, and simulates numerically the wafer deformation of different thicknesses and contact methods. Based on supporting points' transmission method, the relationship between the distribution of points and wafer deformation is studied. Aiming at the minimal deformation, the distribution of supporting points is determined by optimal design method.

This paper presents the electromagnetic model and the experimental results of a novel bond head for chip operation. The existing bond head with spring or mechanical connection is difficult to achieve the purpose of protecting chips. The pneumatic bond head can't timely feedback the force signal to control system. To increase the effective and safety of the die bonding, a bond head with the very fast response and steady bonding force is required. A constant-force bond head with proportion electromagnet is proposed. The magnetic force is studied using a FEM electromagnetic field model, and the structure parameters of bond head are optimized. A design is created that achieves a force error range of 1% in 0.3mm displacement. A prototype of the designed bond head is built. The bonding force measurements and system response time are tested to check the stability. The test results show that the calculated magnetic force agreed fairly well with the measured results, and the force error range of 1% is achieved.

The basic principle, structure, and function of an expert system for designing permanent magnet retarder (PMR) is described. The system takes into account the preliminary design process and has been achieved with a high interactivity level. The frame structure and work mode of the platform are introduced by analyzing function modules. The main parameters of the PMR structure are designed using robust optimization techniques. The functions of the simulation analysis and virtual assembly module are discussed. The expert system of the technology integration is developed.