Lateral current spreading in the 4H-SiC Schottky barrier diode(SBD)chip is investigated.The 4H-SiC SBD chips with the same vertical parameters are simulated and fabricated.The results indicate that there is a fixed sp...Lateral current spreading in the 4H-SiC Schottky barrier diode(SBD)chip is investigated.The 4H-SiC SBD chips with the same vertical parameters are simulated and fabricated.The results indicate that there is a fixed spreading resistance at on-state in current spreading region for a specific chip.The linear specific spreading resistance at the on-state is calculated to be 8.6Ω/cm in the fabricated chips.The proportion of the lateral spreading current in total forward current(Psp)is related to anode voltage and the chip area.Psp is increased with the increase in the anode voltage during initial on-state and then tends to a stable value.The stable values of Psp of the two fabricated chips are 32%and 54%.Combined with theoretical analysis,the proportion of the terminal region and scribing trench in a whole chip(Ksp)is also calculated and compared with Psp.The Ksp values of the two fabricated chips are calculated to be 31.94%and 57.75%.The values of Ksp and Psp are close with each other in a specific chip.The calculated Ksp can be used to predict that when the chip area of SiC SBD becomes larger than 0.5 cm2,the value of Psp would be lower than 10%.展开更多
Cuckoo search （CS）, inspired by the obligate brood parasitic behavior of some cuckoo species, iteratively uses L6vy flights random walk （LFRW） and biased/selective random walk （BSRW） to search for new solutions....Cuckoo search （CS）, inspired by the obligate brood parasitic behavior of some cuckoo species, iteratively uses L6vy flights random walk （LFRW） and biased/selective random walk （BSRW） to search for new solutions. In this study, we seek a simple strategy to set the scaling factor in LFRW, which can vary the scaling factor to achieve better performance. However, choosing the best scaling factor for each problem is intractable. Thus, we propose a varied scal- ing factor （VSF） strategy that samples a value from the range [0,1] uniformly at random for each iteration. In addition, we integrate the VSF strategy into several advanced CS vari- ants. Extensive experiments are conducted on three groups of benchmark functions including 18 common test functions, 25 functions proposed in CEC 2005, and 28 functions intro- duced in CEC 2013. Experimental results demonstrate the ef- fectiveness of the VSF strategy.展开更多
基金This work was supported in part by National Natural Science Foundation of China(62004161)in part by Natural Science Basic Research Plan in Shaanxi Province of China(2020JQ-636)+2 种基金in part by Scientific Research Project of Education Department of Shaanxi Province(20JK0796)in part by Youth talent lift project of Xi’an Science and Technology Association(095920201318)in part by Bidding Project of Shanxi Province(20201101017).
文摘Lateral current spreading in the 4H-SiC Schottky barrier diode(SBD)chip is investigated.The 4H-SiC SBD chips with the same vertical parameters are simulated and fabricated.The results indicate that there is a fixed spreading resistance at on-state in current spreading region for a specific chip.The linear specific spreading resistance at the on-state is calculated to be 8.6Ω/cm in the fabricated chips.The proportion of the lateral spreading current in total forward current(Psp)is related to anode voltage and the chip area.Psp is increased with the increase in the anode voltage during initial on-state and then tends to a stable value.The stable values of Psp of the two fabricated chips are 32%and 54%.Combined with theoretical analysis,the proportion of the terminal region and scribing trench in a whole chip(Ksp)is also calculated and compared with Psp.The Ksp values of the two fabricated chips are calculated to be 31.94%and 57.75%.The values of Ksp and Psp are close with each other in a specific chip.The calculated Ksp can be used to predict that when the chip area of SiC SBD becomes larger than 0.5 cm2,the value of Psp would be lower than 10%.
文摘Cuckoo search （CS）, inspired by the obligate brood parasitic behavior of some cuckoo species, iteratively uses L6vy flights random walk （LFRW） and biased/selective random walk （BSRW） to search for new solutions. In this study, we seek a simple strategy to set the scaling factor in LFRW, which can vary the scaling factor to achieve better performance. However, choosing the best scaling factor for each problem is intractable. Thus, we propose a varied scal- ing factor （VSF） strategy that samples a value from the range [0,1] uniformly at random for each iteration. In addition, we integrate the VSF strategy into several advanced CS vari- ants. Extensive experiments are conducted on three groups of benchmark functions including 18 common test functions, 25 functions proposed in CEC 2005, and 28 functions intro- duced in CEC 2013. Experimental results demonstrate the ef- fectiveness of the VSF strategy.
