Chapter 22: Acting to perform a full set

　　 The sound this time came from the glove box next to it, as if something heavy had fallen.
　　 Upon seeing this, Chen Wanqing shouted: "The valve can be closed."
　　 Xu Qiu calmly tightened the valve.
　　 He was actually mentally prepared. When he tried to open the hatch just now, he noticed that the hatch was actually hanging in the air.
　　Because the vapor deposition cabin is in a vacuum state, there is a pressure difference between the inside and outside of the cabin, so the cabin door will not fall down. Now that the cabin is filled with nitrogen, the internal and external pressures are the same, and the cabin door will naturally fall on the track below and make an impact sound.
　　 The only thing he is not sure about is the specific time required for the vapor deposition chamber to be filled with nitrogen, after all, this is the first operation.
　　 But in order to cooperate with the senpai, he turned his head and put on a surprised expression.
　　 Looking at the conspiracy of senior sister, Xu Qiu asked: "Senior sister, what's the situation? It's not that the instrument is broken."
　　 Chen Wanqing explained with a smile: "When the vapor deposition chamber is filled with nitrogen, the door will pop out. Just now it was the sound of the door hitting the track."
　　 "It turned out to be like this." Xu Qiu suddenly realized.
　　Since the performance has been performed, let's perform a full set.
　　…………
　　 Xu Qiu entered the glove box, opened the hatch, took off the sample holder, and used tweezers to clip the 11 substrates out of the holder one by one and put them into the petri dish.
　　 He picked up a piece of substrate casually and observed that there were six shiny silver aluminum electrodes on the surface of the substrate.
　　Different from the aluminum products seen in life, the surface of aluminum will not be oxidized in a nitrogen atmosphere, so it is not much different from silver in appearance.
　　 "Senior sister, why are these six electrodes vapor-deposited?" Xu Qiu wondered.
"Because a mask is used in the evaporation process," Chen Wanqing explained: "The mask is a stainless steel sheet with a hollow pattern on it. Place it under the sample table. Only in the hollow part, the target molecules can pass. Thereby vapor deposition on the substrate to obtain a specific pattern.
　　 As for why there are six electrodes, it is because six battery devices are integrated on this substrate, and each set of electrodes corresponds to a battery.
　　 To make a simple analogy, you stretch out the index fingers of your left and right hands, cross them, and there will be a square overlap in the middle.
　　Battery devices are also similar. The lower ITO electrode and the upper aluminum electrode are like two fingers. Only where they cross is the effective area of ​​the battery.
　　The area of ​​the effective area must be determined so that we can accurately calculate the photoelectric conversion efficiency of the battery device.
　　Like our substrate, the width of both electrodes is 0.3 cm, so the effective area of ​​a device is 0.09 square cm. "
　　 Suddenly, Chen Wanqing seemed to have thought of something, and said eagerly: "Xu Qiu, take the substrate and show me the back of it."
　　 Xu Qiu didn't quite understand what the senior sister wanted to do, but he still did.
　　 Chen Wanqing carefully observed the substrate and said, "One more piece."
　　 After reading it, the senior sister heaved a sigh of relief and asked: "Did you all face the same direction when you put the substrate?"
　　 "Yes." Xu Qiu said.
　　 When he placed the substrate, he noticed that the ITO pattern on the substrate was 180-degree symmetrical instead of 90-degree symmetrical. However, he didn't think much about it at the time, and directly operated according to the system's images.
"That's good," Chen Wanqing said: "The substrate must be placed in a specific direction. As mentioned earlier, after the two electrodes are crossed, the overlapping part is the effective area of ​​the battery. If you put this batch If the substrate is rotated 90 degrees and then evaporated, the ITO and aluminum electrode ends will be directly connected, and the battery will short-circuit."
　　 "That's not right," Chen Wanqing said puzzledly: "I haven't taught you this, how did you know it."
　　 Xu Qiu was taken aback, yes, I didn't even know the mask just now, so I can't say that I analyzed it by myself.
　　 Since the explanation is not clear, I can only make up a reason.
"The first substrate, I just put it on at that time, and then I thought that this batch of substrates can be considered as a family, so it should be neat and tidy, so I simply put it in the same direction." Xu Qiu sighed. Road:
　　 "Unexpectedly, 50% chance of being hit by me is really lucky."
　　 "Is that really the case?"
"Of course."
at this time.
　　 Xu Qiu thought, but fortunately, the elder sister didn't bother with this problem anymore, and successfully passed the blunder.
　　 Chen Wanqing thought to herself, this is called preemptive diversion, the schoolboy didn't notice at all, and I missed the details of the experiment again.
　　…………
　　 Chen Wanqing checked the phone time, at 4:56 pm, and said:
　　 "There is still more than half an hour to eat. Load the next batch of zinc oxide substrates. Time should come."
　　 Xu Qiu thought about it and asked:
　　 "Didn't it take more than two hours for evaporation?"
　　 "You can go to dinner when you vacuum up, and you can continue after eating." Chen Wanqing said.
　　 "What about the instrument?" Xu Qiu wondered: "Don't you need someone to look at it, what if something goes wrong halfway?"
　　"In theory, when a large instrument is operating, someone should watch it, but our instrument is not dangerous, and an alarm will be issued if the instrument operates abnormally.
　　 So just let Feifei Wu watch outside, UU reading www. She is going to write an article in hurry at uukahnshu.com. Teacher Wei said that she will submit the article next week, and the urging is tight. After we go to the cafeteria to have dinner, just pack one for her. "Chen Wanqing explained.
　　 Xu Qiu nodded and continued to work.
　　 The device structure of the second batch of substrates is: PC[60]BM: PC[70]BM/MoO3/Al.
　　 Therefore, it is necessary to vaporize molybdenum trioxide and aluminum. The former uses a beam source furnace to vaporize and the latter uses electric current heating.
　　 Xu Qiu installed the 10 substrates with the sample holder, put them into the sample table, added molybdenum trioxide powder in the beam source furnace, hung the tungsten basket full of aluminum ingots, closed and screwed the hatch.
　　 Then turn on the mechanical pump and turn on the ultra-vacuum flapper valve.
　　 When the vacuum drops below 20 Pa, close the ultra-vacuum baffle valve and turn on the molecular pump.
　　 Get it done, call it a day.
　　…………
　　 On the way to the cafeteria.
　　 Xu Qiu, Chen Wanqing, Duan Yun and Tian Qing talked while walking.
　　 Xu Qiu took this opportunity to get to know other members of the research group.
　　 "Sister Tian Qing, did you argue that the illustrations on the PPT were painted by yourself?"
　　 "Yes, the drawing is not bad, I used the tablet to draw it."
　　 "Yes, it looks like you."
　　 "I also think I will draw one for you when I have time."
　　……
　　 "Senior Brother Duan Yun, why your research direction is related to thermoelectricity? The others in our group are doing photovoltaics."
　　 "After I graduated from my master's degree, I worked for more than three years, doing 3D printing and thermoelectricity.
　　 Suddenly one day, my brain twitched and I wanted to study for a Ph.
　　 It happened that our boss and Teacher Wei met and recommended me to continue working in the thermoelectric field. "
　　……