What are the failure analysis steps of integrated circuits?
Date：2022-07-29 14:29:47 Views：120
Failure analysis can evaluate the effectiveness of different test vectors, provide necessary supplements for production testing, and provide necessary information basis for verification test process optimization. Failure analysis often requires electrical measurement and advanced physical, metallurgical and chemical analysis methods. The purpose of failure analysis is to determine the failure mode and failure mechanism, put forward corrective measures, and prevent the recurrence of this failure mode and failure mechanism. Failure mode refers to the observed failure phenomena and forms, such as open circuit, short circuit, parameter drift, function failure, etc. Failure mechanism refers to the physical and chemical processes of failure, such as fatigue, corrosion and overstress. The following is a brief analysis of the failure analysis steps of integrated circuits for your reference.
Integrated circuit failure analysis steps:
1. Inspection before opening, appearance inspection, X-ray inspection, scanning acoustic microscope inspection.
2. Unpack for microscopic examination.
3. Electrical performance analysis, defect location technology, circuit analysis and microprobe analysis.
4. Physical analysis, delamination, focused ion beam (FIB), scanning electron microscope (SEM), transmission electron microscope (SEM), VC positioning technology.
1、 Nondestructive failure analysis technology
1. Appearance inspection mainly relies on visual inspection to check whether there are obvious defects, such as whether the plastic grease package is cracked and whether the chip pins are in good contact. X-ray inspection is to use the perspective performance of X-rays to irradiate the tested sample. The defective part of the sample will absorb X-rays, resulting in abnormal X-ray irradiation imaging. X-ray mainly checks whether the lead of integrated circuit is damaged. Select the appropriate wavelength according to the size and structure of electronic components, so as to obtain the appropriate resolution.
2. Scanning acoustic microscope uses ultrasonic wave to detect the internal defects of the sample and find out the location of the internal defects of the sample according to the reflection of ultrasonic wave. This method mainly uses the damage of moisture or high temperature to the device during the plastic packaging of the main integrated circuit, which is often cracks or delamination.
2、 Destructive failure analysis technology
1. There are generally three ways to open the package. With the full stripping method, the integrated circuit is completely damaged, leaving only the complete internal circuit of the chip. The defect is that the internal circuit and leads are all damaged, so the electromotive state analysis can no longer be carried out. Methods the Second Bureau total division method, and the third grinder grinds the resin on the surface of the integrated circuit until the chip. The advantage is that after unsealing, the internal circuit and leads will not be damaged, and the electromotive state analysis can be carried out after unsealing. The third method is to use sulfuric acid spray to achieve the effect of local removal.
2. Defect location, locating specific failure location is an important and difficult item in integrated circuit failure analysis. Failure mechanism and defect characteristics can be found only after defect location.
a. Emission microscope technology has the characteristics of non-destructive, fast and accurate. It uses optoelectronic detectors to detect areas that produce photoelectric effects. Due to the defects in the silicon wafer, the growing electron hole recombination usually occurs, resulting in strong photon radiation.
b. OBIRCH technology is a testing technology that uses laser beam to induce the change of material resistivity. By scanning different materials with laser beam, the resistivity changes of different materials can be obtained. This method can test those reliability hidden dangers inside the metal wiring.
C. Liquid crystal hot spot detection is generally composed of a polarizing microscope, a sample table with adjustable temperature, and a control circuit. When changing from crystal anisotropy to crystal isotropy, the critical temperature energy required is very small, so as to improve the sensitivity. At the same time, the phase transition temperature should be controlled at 30-90 degrees, and the polarization microscope should be used in orthogonally polarized light, which can improve the sensitivity of liquid crystal phase transition reaction.
3. Electrical performance analysis (probe table)
According to the layout and schematic diagram of the decorative circuit, combined with the chip failure phenomenon, gradually reduce the circuit range of the defective part, and finally use the microprobe microscopy technology to locate the defective device. Microprobe detection technology, the function of microprobe is to measure the electrical parameters on the internal devices, such as the voltage, current and volt ampere characteristic curve at the working point. Microprobe technology is usually used together with circuit analysis, which can quickly search for failed devices.
3、 Physical analysis
1. Focused ion beam (FIB) is composed of ion source, ion beam focusing and sample stage. An electron microscope is used to focus the ions into a microwave sized cutter. The fine and precise cutting of focused ion beam, combined with the high-resolution imaging of scanning electron microscope, can well solve the profile problem, and the positioning accuracy can reach less than 0.1um. At the same time, the stress in the profile process is very small, and the integrated circuit is completely preserved.
2. Scanning electron microscope (SEM) uses focused ion beam to bombard the surface of the device, and many electronic signals are generated on the surface. These electronic signals are amplified as modulation signals and connected to the display to obtain the surface image of the device.
Transmission electron microscope (TEM), with a resolution of 0.1nm, can clearly analyze device defects and better meet the analytical requirements of integrated apparatus failure analysis for detection tools.
3. VC positioning technology is based on the primary electron beam or ion beam of SEM or FIB to scan the sample surface. There are different potentials on the surface of the silicon wafer, showing different bright contrasts. Find out the points that are normally bright, so as to locate the failure point.
The above is the related content of "failure analysis steps of integrated circuits" brought by this core creation test. I hope it can be helpful to you. We will bring more wonderful content later. The company's testing services cover: electronic component testing and verification, IC true and false identification, product design and material selection, failure analysis, function testing, factory incoming material inspection, taping and other testing items. Welcome to call Chuangxin testing, and we will serve you wholeheartedly.