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• The front specific contact resistance of the solar cell is the smallest after high temperature rapid firing. • The electrical injection significantly increases the Uoc and narrow the difference of hydrogen passivation during firing process. • The Eff after electric injection is the highest, with an average of 24.42 %, an increase of 0.36 %. In the large-scale production of solar cells, metallization is a very important process, which directly affects the opening-circuit voltage, short-cut current, shunt resistance, and fill factor, thus affecting the efficiency of the solar cell. In this paper, the n-TOPCon process is matched by changing the firing temperature and belt speed of each zone to change the peak temperature and the width of the firing curve. After low-temperature slow firing (A1), the front contact resistance of the solar cell is the largest, and the Uoc and the Eff are the highest. However, after the electric injection, the Uoc and the FF increase are small, and the Eff is low, with an average value of 24.23 % and an increase of 0.04 %. After higher temperature and faster firing (AB2), the front-specific contact resistance of the solar cell is the smallest. Affected by the specific contact resistance, the solar cell has the highest FF, the lowest Uoc, and the lowest Eff. However, the electrical injection significantly increases the Uoc. The Eff after electric injection is the highest, with an average of 24.42 %, an increase of 0.36 %. The H ions in SiN x have different effects of passivation on the wafer under different firing conditions, but the difference is narrowed by the electrical carrier injection of H ions on the surface into the wafer. Therefore, solar cells with excellent electrical performance can be obtained by firing at appropriate peak temperature and firing width, obtaining low contact resistance first, and then increasing the Uoc and Jsc by electric injection. [ABSTRACT FROM AUTHOR]

Abstract: Two kinds of different aligned zinc oxide (ZnO) crystal microtube arrays were prepared on silicon (100) substrates by using of a simple thermal chemical reaction vapor transport deposition method. The synthesizing processes were done by using of heating the mixture of zinc oxide and graphite powders at 1150°C in a quartz tube with one side opened to the air. The O2 gas (99.9%) and air had been introduced as the assistant gases, respectively. Both the flow rates were 100ml/min. And the temperature of the Si (100) substrate region was about 400°C. There is no other metal catalyst on the Si wafers in the process. After growing for 30min, one kind of synthesized sample is trumpet-shaped hexagonal microtube arrays assisted with O2 gas and another produced sample is the uniform hexagonal microtubes only assisted with air. As the increasing of preparing time, their maximal lengths can range from several 10μm to mm scale. The microstructure, room temperature photoluminescence properties and growth mechanism of both aligned microtube arrays were investigated and discussed. [Copyright &y& Elsevier]