Silicon nitride film preparation device

Abstract

The invention discloses a silicon nitride film preparation device which is capable of reducing production cost and avoiding miscuing of copper electrodes. A furnace door is fixed onto a supporting rod, when the furnace door needs to open, a driving device is started to enable a slide block to move along a slide pole, the slide block in movement drives a supporting frame to move so as to drive the supporting rod to move, and since the furnace door is fixed onto the supporting rod, the supporting rod can open the furnace door during movement. Due to the facts that copper electrodes are arranged at the inner center of the furnace door and electrode insert holes are formed in one end, facing the furnace door, of a quartz boat, when the quartz boat is placed, the copper electrodes can be accurately inserted into the electrode insert holes by adjusting placement position of the quartz boat, and miscuing of the copper electrodes due to aimless alignment is effectively avoided. In addition, opening and closing of the furnace door are finished under movement of the supporting rod, the driving device is less prone to damages, and production cost can be greatly reduced. Moreover, the silicon nitride film preparation device is suitable for popularization and application in the field of solar cell silicon chip processing equipment.

Description

technical field [0001] The invention relates to the field of solar cell silicon chip processing equipment, in particular to a silicon nitride film preparation device. Background technique [0002] Since the sunlight is irradiated on the silicon wafer of the solar cell, part of the sunlight will be reflected. Even if the silicon surface is designed as a suede surface, although the incident light will produce multiple reflections to increase the light absorption rate, there will still be Part of the sunlight will be reflected. In order to reduce the reflection loss of sunlight, the usual method is to cover a layer of anti-reflection film on the surface of the silicon wafer of the solar cell. This film can reduce the reflectivity of sunlight and increase the photoelectric conversion. Efficiency, in the technology of depositing anti-reflection film on the surface of crystalline silicon, silicon nitride film has the characteristics of high insulation, good chemical stability, goo...

AI Technical Summary

Problems solved by technology

This silicon nitride film preparation device has the following problems in the actual use process: first, because the furnace door of the device used to prepare silicon nitride film is usually heavy, it is difficult to open or close manually. Into and out of the vacuum deposition chamber, the furnace door is usually provided with a switch device for opening or closing the furnace door. The existing switch device includes a forward motor and a rotating motor. The forward motor is used to move the furnace door It is in contact with and separated from the vacuum deposition chamber. The rotating motor is used to rotate the furnace door to the side of the furnace mouth, allowing space for entering and exiting the vacuum deposition chamber. The forward motor is connected to the furnace door through a push-pull rod, and the rotating motor is rotated through a The rod is connected to the furnace door. During the use of this switch device, there are the following problems: in the switch device of this structure, the rotating motor and the furnace door are respectively located at the two ends of the rotating rod, which makes the rotating motor need to provide a large amount of rotation. Torque can make the furnace door rotate, the rotating torque of the rotating motor is large, the load of the motor is large, it is easy to burn out the rotating motor, the service life of the rotating motor is short, and the motor needs to be replaced frequently, which not only affects the normal production , also greatly increased the production cost, meanwhile, the copper electrode of the existing silicon nitride film preparation device is fixed on the rear end of the vacuum deposition chamber, and the furnace door is arranged on the front end of the vacuum deposition chamber. After the vacuum deposition chamber, the electrode socket set on the end face of the graphite boat needs to be aligned with the copper electrode before it can be energized. However, since the copper electrode is inside the vacuum deposition chamber, we can only keep trying to align it, so it is easy to connect the copper electrode. It is crooked and cannot be matched with the socket, and the matching degree of the insertion is difficult to guarantee, which will easily cause the deposition process to fail smoothly, and it is very inconvenient to maintain; secondly, during the working process of the silicon nitride film preparation device, the vacuum deposition chamber The temperature needs to be kept within a stable range. Since the existing silicon nitride film preparation devices directly pass the mixed gas of ammonia gas and silicon hydride directly into the vacuum deposition chamber, the temperature of ammonia gas and silicon hydride is relatively low. , generally close to room temperature, when the two enter a high-temperature environment with a temperature as high as 400 degrees Celsius, it will inevitably have a greater impact on the temperature in the vacuum deposition chamber. The layers are not uniform, which affects the conversion efficiency of the cell; moreover, the exhaust gas generated during the deposition process of the existing silicon nitride film preparation device is discharged to the In the outside world, because part of the silane cannot fully react during the deposition process, the unreacted silane is mixed with the tail gas and discharged, and the silane gas will spontaneously ignite when it encounters air. Spontaneous combustion will not occur, but once the exhaust gas enters the tailpipe, because the tailpipe is connected with the outside air, the silane contained in the exhaust gas that enters the tailpipe is easy to spontaneously ignite, so that the tailpipe often catches fire, and in severe cases it will It will lead to the explosion of the tailpipe and cause production accidents, and its safety is poor; in addition, the existing silicon nitride film preparation device needs to use a vacuum pump to vacuum the silicon nitride film before the deposition process. The empty deposition chamber is evacuated to a certain degree of vacuum, and then the deposition process is carried out. During the deposition process, the vacuum pump is always working. There is only one discharge pipe with an inner diameter of about 60mm between the vacuum pump of the existing silicon nitride film preparation device and the exhaust port of the vacuum deposition chamber. The effect is better, but during the deposition process, due to the thicker inner diameter of the discharge pipe, the process gas in the vacuum deposition chamber will be quickly pumped away, and some process gas will be pumped away by the vacuum pump before the reaction, so it is necessary to pass Only a large amount of process gas can be injected to ensure the normal progress of the deposition reaction, which will easily cause waste of process gas and increase production costs

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