Chapter 4: Cleaning the substrate

　　 After reading the "Laboratory Safety Manual", Chen Wanqing instructed Xu Qiu to put on his lab coat, disposable PE gloves and activated carbon mask.
　　Everything is ready, she introduced:
　　"The main research field of our research group is solar cells, but mine is mainly in the organic field.
　　 The preparation of solar cell devices in the laboratory requires the use of substrates. The substrate we use is a glass substrate printed with ITO, which is an indium tin oxide pattern.
　　ITO has high electrical conductivity and light transmittance and is a good electrode material.
　　 This kind of substrate is imported from the United States, and the cost is relatively high, about $4 per piece, so Mr. Wei asked us to reuse it. "
　　 Today I will teach you how to clean the substrate. "
　　 "Okay, Senior Sister." Xu Qiu nodded.
　　…………
　　【Detected substrate cleaning skills, whether to record? 】
　　 "Record." Xu Qiu said silently in his heart.
　　 At the same time he noticed that the system interface has been updated.
　　【Scientific Research Support System】
　　 Permission level: 1
　　 Points: 100
　　 Tasks in progress: 1
　　 Proficiency:
　　【Experimental operation class】
　　Clean the substrate (first order 0%/fourth order 50%)
　　【Instruments and equipment】
　　 Ultrasonic Cleaner (Third order 20%/Fifth order 0%)
　　 Tweezers (second order 50%/fourth order 50%)
　　 Nitrogen gun (first order 0%/fourth order 50%)
　　##
　　 The first-order 0%, second-order 50%, and third-order 20% in the front represent Xu Qiu's current proficiency.
　　Because he has been exposed to ultrasonic cleaners and tweezers in the experimental class, he has initial proficiency.
　　 The fourth-order 50% and the fifth-order 0% are the proficiency of the auxiliary system to replicate the operation of the senior sister, which can be roughly regarded as the upper limit that he can reach in the short term.
　　 An experimental operation usually requires the use of multiple instruments and equipment, and its proficiency depends on the least proficiency of these instruments.
　　 unlocked the new function, Xu Qiu couldn’t wait to try it out, so he communicated with the system:
　　 "I want to deduce the cleaning of the substrate from the fourth order 50% to the fifth order. How many points do I need?"
　　【Need 1×50%×1000×2=1000 points. 】
　　 Well, I can't afford it.
　　 He is still a first-order 0% pure cute new, he still works hard to complete the task and accumulate points.
　　 I’ll use Senpai first, I’ll just use it.
　　…………
　　 "Leave it to you, you can call me anytime if you have any questions."
　　 Chen Wanqing demonstrated the operation process again, then handed the remaining old substrates to Xu Qiu and returned to her seat.
　　 "Okay, thank you senior sister."
　　 The master leads the door, and the practice depends on the individual.
　　The road of scientific research starts from the mess.
　　 Xu Qiu first carefully picked up an old substrate and observed it carefully.
　　 The surface of the substrate is square, and some silver-white electrodes and black coating materials are attached to it.
　　 He visually observed that the length and width of this substrate is about 2.5 cm. Considering that it is produced abroad, the specification should be 1 inch, which is 2.54 cm, and the thickness is about 3 mm.
　　 This small piece of glass is worth 30 yuan, and scientific research is a real burn.
　　 He turned on the auxiliary system, selected the "cleaning substrate" item, and started the operation against the image.
　　 The image has been abstracted and processed by the system, and the operator is not a schoolgirl, but a virtual villain.
　　 You can clearly see the operation details of each step, and you can pause, fast forward, adjust the progress, etc. according to your mind.
　　 He quickly enters the state, imitating the video operation.
　　 "First of all, place the old substrate on the holder with tweezers, and be careful not to touch the center of the substrate to prevent scratches."
　　……
　　Because of the experience of using tweezers, Xu Qiu quickly filled a bracket, picked up the bracket and counted, there are 24 pieces in total.
　　【Tweezers proficiency +20%】
　　" Then, put the holder full of old substrates into the box labeled "soap" and pour soapy water until the liquid level is below the holder. Then cover the lid and place it in an ultrasonic cleaner for 20 minutes.
　　 Next, the substrate was sequentially transferred to deionized water, acetone, and isopropanol, and ultrasonically cleaned for 10 minutes each. "
　　 There is no difficulty in these steps. The ultrasonic cleaner only has a master switch, an on/pause button, and four buttons for setting the time.
　　 Just set the time, put the box in, and press the open button.
　　……
　　【Ultrasonic cleaner proficiency +80%】
　　 The process of ultrasonic cleaning of the substrate does not need to be watched all the way, and other tasks can be performed at the same time.
　　 Xu Qiu was not idle either, taking this opportunity to fill up four more brackets.
　　【Tweezers proficiency +40%】
Originally, he wanted to get close to the senior sister, but he could see Chen Wanqing sitting in a chair, sometimes holding his forehead and frowning, sometimes tapping the keyboard quickly, and sometimes flipping through the paper information at hand. In a state of concentration and selflessness, this idea was dispelled.
　　 After four rounds of cleaning, only 14 clean substrates remain.
　　 This is not Xu Qiu's operation problem, but because the attachments on the surface of some old substrates are relatively firm, and it takes multiple rounds of cleaning to clean them.
　　One petri dish can hold 12 substrates. He took out two petri dishes from the cabinet.
　　 View system images:
　　" Finally, use tweezers to clamp the substrate out of the box containing isopropanol. Be careful not to extend the tweezers under the liquid surface to prevent contamination.
　　 Then dry it with a nitrogen gun (can spray nitrogen gas), and put it into a clean petri dish. "
　　 Xu Qiu picked up a pair of tweezers and took a piece of substrate, holding the nitrogen gun in the other hand, and then pressed the switch of the nitrogen gun.
"Snapped."
　　 The substrate was blown off by the nitrogen gas stream and fell onto the table.
　　The dropped substrate will be stuck with impurities such as dust, so it can only be rebuilt and cleaned again by UUReading www.uukānshu.com.
　　 Xu Qiu shook his head and began to analyze the reason:
　　 On the one hand, he used a nitrogen gun for the first time. He did not control the airflow properly. This time the airflow was obviously too large;
　　 On the other hand, he felt that the tweezers on his hand were not firmly clamped.
　　 Is it a problem with your own technique?
　　 He carefully observed the image again, and finally found that the tweezers he used were different from the tweezers used in the image.
　　 One head is pointed, the other is flat.
　　 Putting down the pointed tweezers in his hand, Xu Qiu chose a flat tweezers again.
　　 tried again, and sure enough the new tweezers picked up the substrate to be much more stable.
　　……
　　 A total of 11 washed and blown substrates were obtained.
　　 Xu Qiu was inexperienced, so he blew two pieces away again.
　　【Tweezers proficiency +10%】
　　【Nitrogen Gun Proficiency +120%】
　　 originally prepared two petri dishes, but not even one was filled.
　　 After completing a set of procedures, Xu Qiu opened the system page.
　　【Scientific Research Support System】
　　 Permission level: 1
　　 Points: 100
　　 Tasks in progress: 1
　　 Proficiency:
　　【Experimental operation class】
　　Cleaning the substrate (20% for the second order / 50% for the fourth order)
　　【Instrument equipment tools】
　　Ultrasonic cleaner (fourth order 0%/fifth order 0%)
　　 Tweezers (third order 20%/fourth order 50%)
　　 Nitrogen gun (second order 20% / fourth order 50%)
　　##
　　 Seeing the rapid increase in proficiency, Xu Qiu was very satisfied.
　　He held a petri dish with a clean substrate and handed it to the senior sister for acceptance.