Search

As equipment usage environments become increasingly complex and harsh, the reliability of chips as the core of high-density integrated circuits becomes increasingly important. Bond wires, as weak links, are the focus of reliability research. Traditional research has focused on permanent failures, while intermittent failures have received little attention due to their unpredictable nature, but their existence cannot be ignored. This article simulates temperature shock and vibration environments on bond wires, demonstrating that the dangerous area of bond wires is located at the junction of the gold wire and the chip solder pad. It also explains that intermittent failures are caused by the degradation or potential damage of bond wires that are further damaged when subjected to environmental shocks, with the effective contact area of the damaged area changing with the shock and the resistance changing significantly. Based on the theory of contact resistance, relevant models were constructed for simulation, and the effect of micro-protrusion depth on contact resistance was studied. The article then designed and constructed an experimental circuit to carry out intermittent failure verification tests and studied the characteristics of intermittent failure currents. This research provides theoretical and technical support for the study of intermittent failures in high-density integrated circuits. • Simulation software is used to study the intermittent faults caused by chip bonding lines. • The weak part of the bond line under temperature and vibration impact is studied. • The change of contact resistance at the crack of the bond line was studied. • Intermittent fault signals are obtained using dynamic currents. [ABSTRACT FROM AUTHOR]

Poly(phthalazinone ether ketone) (PPEK) is noted for its outstanding heat-resistance property and mechanical strength. A one-step electrospinning method was conducted to produce PPEK micro-nano porous fibrous mat. We gave emphasis study on the spinnability, optimized conditions, fibers’ morphology, surface science and fracture mechanism. The uniform electrospun fibrous mat resulted from PPEK/chloroform binary system indicated that PPEK would be a prospective material to be applied in electrospinning. Addition of a small amount of non-solvent (ethanol) turned out to be advantageous to the reduction of fiber diameter and the alleviation of choking during spinning process. Organic salt (benzyltrimethylammonium chloride) was employed to increase the conductivity of solution for the formation of thin fiber. After trials, PPEK/chloroform/ethanol system with salt and PPEK/NMP system were taken as two optimized systems. These two systems showed different pore fraction in N 2 adsorption test, and displayed different mechanical behaviors in uniaxial tension test. The fibrous mat from PPEK/chloroform/ethanol system showed a feature of ductile fracture with relatively low fracture strength but long fracture deformation, while the fibrous mat from PPEK/NMP system showed a feature of brittle fracture with small deformation but quite large fracture strength of ca. 6 MPa. Finally thermogravimetric analysis indicated that the resultant PPEK fibrous mat did not decompose until the temperature reached 478 °C, which qualified the resultant fibrous mat as a promising material used under high-temperature condition. [ABSTRACT FROM AUTHOR]