Papers by Keyword: Defect Analysis

Abstract: With the advent of EUV lithography and other emerging processes such as area selective deposition, and SOIC hybrid bonding, the need to identify the chemical composition of defects is of paramount importance. The defects of concern range from 10nm to 500nm in lateral size and as thin as ~ 1 nm in thickness, which the current batch of molecular analytical tools cannot address adequately since the indications are that many of the defects and residues detected are organic in nature. In this paper, a relatively new nanoscale technique called infrared photo-induced force microscopy (IR PiFM), which combines non-contact atomic force microscopy (AFM) and infrared (IR) spectroscopy with ~ 5 nm spatial resolution, is introduced. The paper will show how the nanoscale hyperspectral IR PiFM data can provide unambiguous and speedy feedback to process engineers engaged in EUV lithography and other advanced semiconductor processes.

Abstract: In the experiments of different process parameters (laser power, scanning speed and scanning distance),the low-time defects of forming part were studied by microscope,including air bubble, pore, micro-crack and macro-crack. The formation mechanism of bubble-defect was analyzed.Linear energy density (E=P/v) was introduced as synthetic parameter.According to analysis and test verification, the optimum technological parameters of 316L stainless steel were laser power 190-210KW, laser speed 800-1000mm/s and scanning interval 0.9-0.11mm,and the linear energy density was about 200J/m. There were no cracks, no bubbles, a small amount of porosity, and the product density reached 99.7%.

Abstract: With different process parameters (laser power, scanning speed and scanning distance),the low-time defects of forming part were studied by microscope,including air bubble, pore, micro-crack and macro-crack. The formation mechanism of pore-defect was analyzed. The micro-structure and composition of the pore-defect were studied by means of SEM and EDS. The results showed that the porosity mainly included circular air porosity, irregular process porosity and oxide inclusion.Linear energy density (E=P/v) was introduced as synthetic parameter.According to analysis and test verification, the optimum technological parameters of 316L stainless steel were laser power 190-210KW, laser speed 800-1000mm/s and scanning interval 0.9-0.11mm,and the linear energy density was about 200J/m. There were no cracks, no bubbles, a small amount of porosity, and the product density reached 99.7%.

Abstract: This paper describes a typical 3D X-ray micro computed tomography (microCT) analysis of light metal parts, from a radio controlled airplane engine. This case study shows the power of 3D X-ray inspection and analysis for this type of material, including information about the size and location of casting defects, the location of turbine blade balancing weights and dimensional measurements indicating the axle was not perfectly centre. Advantages and limitations of the method for light metals are described in general

Abstract: Die-casting process is significantly used in the industry for its high productivity and less post-machining requirement. For high pressure die-casting, it needs well-design of gating and runner system; therefore, die cavity design and technology parameter calculations are essential. In the current paper of die-casting for automobile starter motor casing, the following issues are focused: filling simulation, defect analysis, and finally the use of the Taguchi multi-quality analysis method to find the optimal parameters and factors to increase the aluminum ADC10 die-casting quality and efficiency. When the casting speed is increased, the volume shortage detects due to solidification procedure can be reduced. However, if the casting speed exceeds a permissible level, the defects of gas volume and porosity will occur. After Taguchi method analysis, the results of the optimum parameters are: for the gate area of 40mm², group 2 of the gate location, the speed of the liquid metal at the gate 50 m/s, the temperature of molten aluminum 670° C.

Abstract: The filling and solidification process of casting that is closely related to lots of casting defects and has significant effect on the mechanical properties of castings. In this paper, the research status and development direction of numerical simulation technology of casting, especially of lost foam casting were reviewed and discussed. Also a brief introduction of the basic situations and product characteristics of several outstanding cast filling and solidification simulation softwares were summarized. In addition, the actual domestic application status of numerical simulation technology of lost foam casting in the foundry enterprises was analyzed and some suggestions were given as well.

Abstract: The defects of material, packaging process and layout in power electronic packaging modules can affect the temperature distribution. Defects such as the voids of the welding and the unreasonable layout will cause uneven distribution of the temperature field in the internal surface and the local hot spots will emerge. If the hot spots continued, the module will be damaged. In order to achieve the defect analysis based on the temperature field, a test system is designed. The infrared camera is used to measure the temperature distribution in the system. The system can test the temperature field distribution characteristics with different loads. The study provided a strong basis of defect analysis standards based on temperature field.

Abstract: Winding temperature rise is inevitable for electrical equipment. There is no harm when device is working properly. However, winding temperature rise will be abnormal when equipment failure exists, this will affect the normal operation of equipment even cause electrical accidents. According to the principle of winding temperature rise, we designed an experiment in which the winding temperature rise is real-time monitoring by the thermal infrared imager. Then we get the data and analysis them,after all we simulated the procedure of monitoring and troubleshooting by infrared technology for equipment in electrical system.

Abstract: The paper introduces the major defects and its causes of solid rocket motor,the harm and effects of the combustion chamber defects for the stability of motor were clarified,the main methods and their advantages and disadvantages of defect detection currently used in solid rocket motor are also cited and analyzed, and it points out the developing trends about various of detection technology used in conjunction.

Abstract: To a great extent，traffic accidents of liquefied gas tankers are caused by the defects inside the tankers themselves. Analyzing what causes the defects, and putting forward the corresponding prevention measures, to reduce accident risk, is of great significance. In this paper, the research object is a defective liquefied gas tanker in a propylene factory in Shandong. The defects in actual transportation process containing weld joints defects and anti-wave plates are analyzed, and the corresponding solutions are put forward on the basis of the literature analysis. The results show that the main causes of the defects are that the manufacture and processing did not correspond with design data. The defects repair of the liquefied gas tanker should be performed by qualified service units after specific repair plan and relevant formalities are put forward. The repaired liquefied gas tanker should be inspected qualified by the inspection organizations.