IC chip failure analysis, IC chip integrated circuit can not avoid failures in the process of development, production and use. With the improvement of product quality and reliability requirements, failure analysis work is becoming more and more important. Through chip failure analysis, IC chip The designer can find design defects, inconsistencies in technical parameters, improper design and operation and other issues. The main meaning of failure analysis is:
In detail, the main significance of IC chip failure analysis is shown in the following aspects:
1. Failure analysis is an important means and method to determine the failure mechanism of IC chips.
2. Fault analysis provides necessary information for effective fault diagnosis.
3. Failure analysis provides design engineers with continuous improvement and improvement of chip design to make it meet the needs of design specifications.
4. Failure analysis can evaluate the effectiveness of different testing methods, provide necessary supplements for production testing, and provide necessary information for optimization and verification of the testing process.
The main steps and content of failure analysis:
◆Integrated circuit unpacking: Remove the integrated circuit while maintaining the integrity of the chip's functions, maintaining die, bondpads, bondwires and even lead-frame, to prepare for the next chip invalidity analysis experiment.
◆SEM scanning mirror/EDX composition analysis: material structure analysis/defect observation, element composition routine micro-area analysis, accurate measurement of composition size, etc.
◆Probe test: The electrical signal inside the IC can be obtained quickly and conveniently through the micro-probe. Laser: Use a micro laser to cut a specific area on the upper part of the chip or line.
◆EMMI detection: EMMI low-light microscope is a high-efficiency fault analysis tool, which provides a high-sensitivity and non-destructive fault location method. It can detect and locate very weak luminescence (visible light and near-infrared light), and capture the leakage current caused by various component defects and abnormalities.
◆OBIRCH application (laser beam-induced impedance change test): OBIRCH is often used for high-impedance and low-impedance analysis inside IC chips, and line leakage path analysis. The OBIRCH method can effectively locate the defects in the circuit, such as the holes in the lines, the holes under the through holes, the high resistance area at the bottom of the through holes, etc. It can also effectively detect short circuits and leakage, which is a powerful light-emitting microscopy technology. Follow-up supplement.
◆LCD hot spot detection: Use the LCD screen to detect the molecular arrangement and recombination of the IC leakage, and display a patchy image different from other areas under the microscope to find the leakage point that will trouble the designer in the actual analysis (the fault point is greater than 10mA). Fixed-point/non-fixed-point chip grinding: Remove the gold bumps implanted on the LCD driver chip Pad, so that the Pad is completely intact, which is conducive to subsequent analysis and rebonding.
◆X-Ray non-destructive testing: Detect various defects in IC chip packaging, such as peeling, bursting, voids, wiring integrity, PCB manufacturing process may have some defects, such as poor alignment or bridging, open circuit, short circuit or abnormality Defects in the connection, integrity of the solder balls in the package.
◆SAM (SAT) ultrasonic flaw detection can non-destructively detect the internal structure of IC chip package, and effectively detect various damages caused by moisture and heat, such as O crystal element surface delamination, O tin ball, crystal element or filler The gaps in the O packaging material, the pores in the O packaging material, O various holes such as the wafer joint surface, solder balls, fillers, etc.
