Eleven groups of wire bonding experiments are carried out on an experiment platform (restructured with a U3000 heavy aluminum wedge wire bonder). Pure silicon aluminum wire (300 μm in diameter, 2.94-3.92 N in aver...Eleven groups of wire bonding experiments are carried out on an experiment platform (restructured with a U3000 heavy aluminum wedge wire bonder). Pure silicon aluminum wire (300 μm in diameter, 2.94-3.92 N in average pull force) and nickel coated aluminum substrates are used in the experiments. During the experiment process, only ultrasonic power rate parameter is changed and the other bonding parameters are kept as constant, The bonding force and time are 4.90 N and 100 ms respectively. After the bonding experiments, shear strength tests are carried out on the bonds as the bonding strength criterion. From those experiments and test results, some conclusions are obtained: In the small ultrasonic power rate conditions (about 20%-30%), with the power increasing, the bonding strength enhances accordingly; However, in the large ultrasonic power rate conditions (about 45%-70%), the bonding strength decreases accordingly and over bonding happens. Only when the ultrasonic power rate is in a moderate condition (about 35%-40%) can good and stabilized bonding strength be acquired.展开更多
Single event gate rupture(SEGR) is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimenta...Single event gate rupture(SEGR) is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimental results show that SEGR can also happen in the gate bus regions.In this paper,we used simulation tools to estimate three structures in power MOSFETs,and found that if certain conditions are met,areas other than cell regions can become sensitive to SEGR.Finally,some proposals are given as to how to reduce SEGR in different regions.展开更多
基金This project is supported by National Natural Science Foundation of China (No.50390064)National Basic Research Program of China(973 Program,No.2003CB716202).
文摘Eleven groups of wire bonding experiments are carried out on an experiment platform (restructured with a U3000 heavy aluminum wedge wire bonder). Pure silicon aluminum wire (300 μm in diameter, 2.94-3.92 N in average pull force) and nickel coated aluminum substrates are used in the experiments. During the experiment process, only ultrasonic power rate parameter is changed and the other bonding parameters are kept as constant, The bonding force and time are 4.90 N and 100 ms respectively. After the bonding experiments, shear strength tests are carried out on the bonds as the bonding strength criterion. From those experiments and test results, some conclusions are obtained: In the small ultrasonic power rate conditions (about 20%-30%), with the power increasing, the bonding strength enhances accordingly; However, in the large ultrasonic power rate conditions (about 45%-70%), the bonding strength decreases accordingly and over bonding happens. Only when the ultrasonic power rate is in a moderate condition (about 35%-40%) can good and stabilized bonding strength be acquired.
文摘Single event gate rupture(SEGR) is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimental results show that SEGR can also happen in the gate bus regions.In this paper,we used simulation tools to estimate three structures in power MOSFETs,and found that if certain conditions are met,areas other than cell regions can become sensitive to SEGR.Finally,some proposals are given as to how to reduce SEGR in different regions.