WO2023088173A1 - 一种气体扩散方法 - Google Patents

一种气体扩散方法 Download PDF

Info

Publication number
WO2023088173A1
WO2023088173A1 PCT/CN2022/131310 CN2022131310W WO2023088173A1 WO 2023088173 A1 WO2023088173 A1 WO 2023088173A1 CN 2022131310 W CN2022131310 W CN 2022131310W WO 2023088173 A1 WO2023088173 A1 WO 2023088173A1
Authority
WO
WIPO (PCT)
Prior art keywords
nitrogen
furnace
gas
furnace tube
oxygen
Prior art date
Application number
PCT/CN2022/131310
Other languages
English (en)
French (fr)
Inventor
林佳继
祁文杰
梁笑
范伟
毛文龙
卢佳
Original Assignee
拉普拉斯新能源科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 拉普拉斯新能源科技股份有限公司 filed Critical 拉普拉斯新能源科技股份有限公司
Publication of WO2023088173A1 publication Critical patent/WO2023088173A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/22—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities
    • H01L21/223—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities using diffusion into or out of a solid from or into a gaseous phase
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/67005—Apparatus not specifically provided for elsewhere
    • H01L21/67242—Apparatus for monitoring, sorting or marking
    • H01L21/67253—Process monitoring, e.g. flow or thickness monitoring
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/1804—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof comprising only elements of Group IV of the Periodic Table
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/547—Monocrystalline silicon PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present application relates to the fields of semiconductor manufacturing and solar photovoltaic cell manufacturing, for example, a gas diffusion method.
  • the preparation equipment of photovoltaic cells such as diffusion furnace, annealing furnace, oxidation furnace, low pressure chemical vapor deposition (Low Pressure Chemical Vapor Deposition, LPCVD), plasma enhanced chemical vapor deposition (Plasma Enhanced Chemical Vapor Deposition, PECVD), etc. It is to use multi-tube equipment, and multi-tube equipment shares a clean table and loading and unloading equipment. Diffusion is an important process in the preparation of PN junctions.
  • the diffusion method is as follows: put the silicon wafer into the quartz boat, push the quartz boat with the silicon wafer into the tubular diffusion furnace tube, raise the temperature of the diffusion furnace to the first preset temperature, and pass the The temperature of the process gas is maintained for a certain period of time, the source deposition is performed, the flow of the process gas is stopped, and the temperature is changed to the second preset temperature for source expansion.
  • the present application provides a gas diffusion method, which can improve the concentration difference of local dopant sources and improve the square resistance uniformity of silicon wafers.
  • the application provides a gas diffusion method, comprising:
  • the duration is 5-20 minutes, oxygen and nitrogen are introduced during the heating process, and the furnace tube pressure is 150-170mbar;
  • Cool down pass nitrogen to return to normal pressure, and send the boat loaded with silicon wafers out of the furnace.
  • Figure 1 is a schematic diagram of the relevant air intake method (the change of air flow is shown in the figure).
  • Fig. 2 is a schematic diagram of the air intake method of the present application (the change of the airflow is shown in the figure).
  • Fig. 3 is a schematic diagram of the structure of the even flow barrel.
  • Fig. 4 is a schematic view of the structure of the even flow bucket viewed from another direction (the figure shows the connection structure between the transverse connector and the cylinder).
  • Fig. 5 is a schematic diagram of the installation of the uniform flow device inside the furnace tube (an installation example is shown in the figure).
  • Fig. 6 is a schematic diagram of the structure of the gas supply pipe inside the furnace tube (other components in the furnace tube are hidden in the figure).
  • the diffusion method provided in this embodiment includes:
  • No. 1 and No. 2 boats correspond to the first temperature zone, and the temperature in the first temperature zone is adjusted to 795°C.
  • Boat No. 3 corresponds to the second temperature zone, and the temperature in the second temperature zone is adjusted to 780°C.
  • the first temperature zone and the second temperature zone are the positions of the thermal fields corresponding to the 1st, 2nd and 3rd boats.
  • FIG. 2 The schematic diagram of the air intake mode adopted in this embodiment is shown in Figure 2, wherein, 1 represents the rear uniform flow plate (the uniform flow plate in the related art, the plate surface is provided with small holes), 2 represents the furnace tube, and 3 represents the thermal field , 4 represents the furnace mouth insulation board, 5 represents the furnace door, 6 represents the paddle, 7 represents the exhaust pipe, 8 represents the air intake pipe, and 9 represents the gas supply pipe.
  • 1 represents the rear uniform flow plate (the uniform flow plate in the related art, the plate surface is provided with small holes)
  • 2 represents the furnace tube
  • 3 the thermal field
  • 4 represents the furnace mouth insulation board
  • 5 represents the furnace door
  • 6 represents the paddle
  • 7 represents the exhaust pipe
  • 8 represents the air intake pipe
  • 9 represents the gas supply pipe.
  • the original uniform flow plate is removed, and a uniform flow device is added at the end of the furnace.
  • Gases such as N 2 , O 2 , and POCl 3 enter the furnace tube through the uniform flow device; so that the gas enters the furnace tube Afterwards, it is dispersed evenly to prevent the airflow from directly impacting the silicon wafer.
  • the uniform flow device can adopt the uniform flow bucket described in Embodiment 1a, and the uniform flow bucket is 10 cm away from the end of the inlet pipe at the rear of the furnace.
  • the uniform flow bucket is designed in a barrel shape as shown in Figure 3-4.
  • an air supply pipe is added, and the air supply pipe is inserted from the furnace tail to the furnace mouth.
  • a quartz gas supply pipe is used.
  • One end of the gas supply pipe close to the furnace mouth is closed, and the end of the gas supply pipe far away from the furnace mouth is open for feeding gas.
  • the gas supply pipe is provided with a gas outlet.
  • the gas fed into the gas supply pipe is at least one of inert gas and nitrogen.
  • the structure of the gas supply pipe is as described in Embodiment 2a, as shown in Figure 6, the gas supply pipe extends from the furnace tail of the furnace tube to the furnace mouth, the gas inlet at the furnace tail end is ventilated, and the furnace mouth port is closed.
  • the gas supply pipe inside the pipe is provided with a gas outlet.
  • the No. 1 boat is close to the heat insulation board of the furnace mouth, and No. 2, 3, 4...8 boats are arranged in sequence toward the furnace tail.
  • the opening is a circular hole, and in other embodiments, the shape of the opening can be set to other shapes.
  • step (4) is modified to:
  • the nitrogen gas is fed only when the source is turned on (that is, the nitrogen compensation is turned on), and the rest of the time is turned off, and the nitrogen gas feeding time is consistent with the power source time.
  • an inert gas such as helium, is introduced into the gas supply tube.
  • step (4) is modified to:
  • step (4) is modified to:
  • the present embodiment provides a flow equalizer, which adopts a barrel structure, including a barrel body 1a, a first end opening of the barrel body 1a (this is the first opening 7a), and a barrel body 1a.
  • the second end of the body 1a is connected to the sealing surface (that is, the second end of the barrel body is closed), and the sealing surface 2a is provided with an opening 3a.
  • the barrel body 1a can gather the gas entering the uniform flow device to prevent the gas from spreading around; the gas flows out from the opening 3a on the closed surface 2a and is evenly dispersed to prevent the air flow from directly impacting the silicon wafer, which can improve the furnace The inter-chip difference in the square resistance of the upper, middle and lower silicon wafers.
  • the shape of the opening 3a may be a circle, an ellipse, a square, a triangle and the like.
  • the number of openings can also be set according to actual needs.
  • the shape of the opening is circular.
  • the lower part of the flow uniform device is provided with a support 4a
  • the support 4a is fixedly connected with the barrel body 1a
  • the support 4a can support the entire flow uniform device
  • the support 4a It can be used to stably place the uniform flow device in a certain position, for example, the uniform flow device can be placed inside the furnace tube.
  • the shape of the support member 4a matches the shape of the placement area inside the furnace tube, which is conducive to stably placing the flow uniform device inside the furnace tube.
  • the support member 4a is cylindrical, and the cylindrical support member 4a matches the contact portion of the circular furnace tube.
  • the flow equalizer includes two cylindrical supports 4a.
  • the support member 4a is hollow inside, and the first end of the support member 4a is open (this is the second opening 8a), and the support member 4a can be sleeved on the corresponding fixing member 6a, as shown in Figure 3-4, the opening direction of the support 4a is opposite to that of the barrel 1a, the flow equalizer is placed inside the furnace tube, and the support 4a is set on the fixing piece inside the furnace tube. Because the inside of the support member 4a is hollow, it can also reduce the weight of the entire even flow barrel.
  • Fig. 5 shows an installation method of the flow uniforming device, the support member is sleeved on the fixing member 6a to realize the connection between the flow uniforming device and the furnace tube. In other embodiments, other methods can be used for installation, such as installation similar to buckle installation. There is a slot inside the furnace tube, which can cooperate with the support to realize the connection between the flow uniform device and the furnace tube.
  • the uniform flow device in this application when in use, can allow the gas to pass through the opening 3a on the closed surface first, and then flow out through the barrel body; it can also let the gas pass through the barrel body 1a first, and then flow out from the opening 3a.
  • the flow uniforming device further includes a connecting piece 5a, the connecting piece 5a is connected to the supporting piece 4a, the connecting piece 5a is configured to be grasped by the user, and the connecting piece 5a is connected to the supporting piece 4a.
  • the pieces 4a are connected together so that the whole structure is relatively stable.
  • the connecting piece 5a can be in various shapes, for example, it can be any one of square connecting piece, arched connecting piece, transverse connecting piece, etc. or a combination of several shapes.
  • the shape of the connector 5a is similar to an arched handle. As shown in FIG. 4, the two ends of the connector 5a are respectively connected to the second ends of the two cylindrical supports 4a.
  • the connector 5a is convenient for the user to grasp. It is beneficial to take or place the uniform flow device in the furnace tube.
  • the connecting piece 5a is located on the opening side of the barrel body 1a, which can balance the weight distribution of the whole device and make the whole structure more stable.
  • the uniform flow device is placed at the inlet end of the furnace tube, and the uniform flow device is 10-15cm away from the inlet end, which can increase the contact area between the gas and the uniform flow barrel and better disperse the airflow .
  • the closed surface 2a is not provided with openings 3a on the entire surface, and the shape of the area of the openings 3a corresponds to the shape of the boat (set according to the shape of the boat), which is conducive to more concentrated gas Go to the boat instead of drifting away from the boat.
  • the barrel-shaped flow equalizer has better stability in the furnace tube and will not shake, and the even flow device includes a connecting piece 5a, which facilitates putting the flow even device into and taking it out of the furnace tube.
  • the air intake structure further includes a gas supply pipe configured to be capable of supplementing gas, and the gas may be at least one of nitrogen and an inert gas.
  • the air supply pipe is mainly used to supplement nitrogen.
  • the gas supply pipe adopts the form of a plug, and the gas supply pipe is inserted into the furnace tube from the furnace tail and extends to the furnace mouth; the end of the gas supply pipe close to the furnace mouth is closed, and the end of the gas supply pipe away from the furnace mouth is open (this is The third opening 9a) is provided for the passage of gas.
  • the gas supply pipe is provided with a gas outlet 10a. Open the gas outlet on the gas supply pipe, and the gas outlet position can be an area with low square resistance. By increasing the concentration of local nitrogen to dilute the phosphorus source or boron source, the effect of increasing the square resistance can be achieved.
  • the gas outlet 10a is located directly above the gas supply pipe, and the shape of the gas outlet 10a is a round hole with a diameter of 1.5 mm.
  • the gas outlet 10a may not be located directly above the gas supply pipe , can be located obliquely above the gas supply pipe or in other directions, and the specific position of the gas outlet 10a can be set according to actual needs.
  • the shape of the gas outlet 10a may be square, elliptical, etc.
  • the gas outlet 10a is located directly above the intake pipe, the shape of the gas outlet is a round hole with a diameter of 1.5 mm, and the number of gas outlets 10a is 6, which is a combination of 3, 2, and 1.
  • the air supply pipe passes under the even flow device and extends to the bottom of the furnace mouth boat. .
  • the diameter of the air supply pipe is 12mm. In other embodiments, the diameter of the air supply pipe can be other values, which can be set according to specific needs.
  • an air supply pipe in the step of supplying the source, can be added to supply nitrogen; in some embodiments, the compensation flow rate of nitrogen gas is set at 0.5-2 L/min in the step of supplying the source.
  • the gas inlet structure in this application can be used for phosphorus diffusion as well as boron diffusion.
  • the square resistance range difference of embodiment 3 is the smallest.
  • the concentration of the dopant source near the furnace mouth is diluted and reduced by supplementing nitrogen, and the concentration of the dopant source will also be reduced.
  • the airflow is mixed and pushed upwards, which reduces the influence of the suction port on this place, reduces the difference in concentration, and thus reduces the extreme difference in square resistance of the silicon wafer.
  • This application solves the inhomogeneity of the square resistance of the silicon wafer near the gas extraction port by adding gas to the silicon chip near the gas extraction port (the end of the tail pipe in the furnace tube), and reduces the extreme difference in the square resistance.
  • it is necessary to discard part of the silicon wafers near the gas extraction port and reduce the loading of silicon wafers in a single tube to obtain the uniformity of the entire tube.
  • the extremely poor square resistance of the silicon wafer near the gas extraction port can be directly improved, so that the uniformity of the silicon wafer can reach the qualified area, and the production capacity can be improved.
  • the gas flow at the furnace mouth is biased towards the rear exhaust port, resulting in a large air flow at the silicon wafer under the furnace mouth.
  • the density of the doping gas is generally high, it sinks in the mixed gas, causing the furnace
  • the concentration of gas in the lower part of the mouth is high, and the flow rate is large, which leads to a small square resistance of the lower part of the silicon wafer, and a large difference in the square resistance of the silicon wafer.
  • Related methods adjust the pressure of the furnace tube, improve the air flow ratio, and change the temperature of the silicon wafer at the furnace mouth to improve the abnormal square resistance of the silicon wafer at the furnace mouth.
  • Such relative adjustments can slightly reduce the variance, but the improvement is limited if the rest of the silicon remains stable.
  • reduce the number of silicon wafers at the gas outlet to achieve the consistency of the whole tube of silicon wafers.
  • a nitrogen pipeline is added at the furnace mouth, and nitrogen gas is filled at the bottom, as shown in Figure 2, which can not only dilute the high-concentration dopant gas at the gas outlet, but also push the airflow here upwards to mix evenly, reducing the exhaust Tube to the pumping force here.
  • the temperature of the thermal field here by adjusting the temperature of the first temperature zone and the second temperature zone to adjust the square resistance of the boat
  • silicon wafers with extremely small square resistance differences can be obtained.
  • the diffusion method provided by the present application can improve the uniformity of the diffusion square resistance, reduce the extreme difference of the square resistance, and increase the production capacity of the equipment.
  • the production capacity and the uniformity of silicon wafers can be improved by improving the uniformity of the furnace mouth, without increasing the length of the furnace tube, keeping the silicon wafers away from the unstable air flow area, saving machine space and machine manufacturing cost.
  • the closed surface of the uniform flow device is not provided with openings on the entire surface, and the shape of the opening area corresponds to the shape of the boat (it can be set according to the shape of the boat), which is conducive to the more concentrated gas going to the boat and Not drifting off the side of the boat.
  • the barrel-shaped uniform flow device has better stability in the furnace tube and will not shake, and the addition of connecting parts makes it easy to put in and take out from the furnace tube.
  • the air supply pipe is used to supplement nitrogen, which can improve the uniformity of the position of the air extraction port without changing the relevant air extraction structure, and has almost no effect on the square resistance in other boats. It can realize independent air-conditioning area square resistance. The uniformity of the resistance after diffusion is better, which is conducive to the matching of subsequent processes, and the overall electrical performance is also more stable.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Electromagnetism (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

本申请公开了一种气体扩散方法，在炉管进气端增加匀流装置并在通源时在近出气口处补充氮气，稀释掺杂源，将气体混合并推动。

Description

一种气体扩散方法
本申请要求在2021年11月17日提交中国专利局、申请号为202111359969.4的中国专利申请的优先权，该申请的全部内容通过引用结合在本申请中。
技术领域
本申请涉及半导体制造及太阳能光伏电池制造领域，例如涉及一种气体扩散方法。
背景技术
光伏电池片的制备设备，如扩散炉、退火炉、氧化炉、低压力化学气相沉积(Low Pressure Chemical Vapor Deposition，LPCVD)、等离子体增强化学的气相沉积(Plasma Enhanced Chemical Vapor Deposition，PECVD)等大多是使用多管设备，多管设备共用一个净化台和上下料设备。扩散是制备PN结的重要工艺过程。相关技术中，扩散方法是：将硅片放入石英舟中，将在有硅片的石英舟推送入管式扩散炉管内，将扩散炉升温至第一预设温度，向扩散炉内通入工艺气体，保持温度一定时长，进行源沉积，停止通入工艺气体，更改至第二预设温度，进行源扩。
扩散工艺，无论是水平放片还是竖直放片的扩散工艺，无论炉口进气炉尾抽气或者炉尾进气炉口抽气，出气口或进气口会出现方阻不均匀，极差很大。相关方法有2种，(1)减少硅片量，避免不良比例；(2)通过压力、气体流量等来调整方阻不均匀性。但效果都不明显，甚至会影响原本方阻均匀区域的硅片。
发明内容
本申请提供一种气体扩散方法，能够改善了局部掺杂源的浓度差异，提高了硅片方阻均匀性。
本申请提供一种气体扩散方法，包括：
将载有硅片的舟送入炉管中，将匀流装置放置于炉管内部，匀流装置靠近炉尾部。
对炉管抽真空并检漏；
将炉管升温至770-790℃后，往炉管通入氧气和氮气，炉管压力为 150-170mbar；
保持恒温770-790℃，将混合氧气、大氮和携带POCl 3源的小氮从炉尾进气，炉管压力为150-170mbar；
由770-790℃斜率升温至800-1000℃，时长为5-20min，升温过程中通入氧气和氮气，炉管压力为150-170mbar；
保持恒温800-1000℃，时长为5-10min，在恒温的过程中，补充氮气，炉管压力为150-170mbar；
降温，通氮气回到常压，将载有硅片的舟送出炉。
附图说明
图1是采用相关进气方式的示意图(图中显示出了气流的变化)。
图2是本申请进气方式的示意图(图中显示出了气流的变化)。
图3是匀流桶的结构示意图。
图4是从另一个方向看，匀流桶的结构示意图(图中显示出了横向连接件与圆柱的连接结构)。
图5是匀流装置安装在炉管内部的示意图(图中显示出了一种安装示例)。
图6是补气管在炉管内部的结构示意图(图中隐去了炉管中其他部件)。
具体实施方式
以下结合附图对本申请做详细说明，应当指出的是，具体实施方式只是对本申请的详细说明。
实施例1
以磷扩散为例，本实施例提供的扩散方法，包括：
(1)将载有硅片的舟送入炉管中；
(2)对炉管抽真空并检漏；
(3)将炉管升温至770-790℃(可选770℃)后，往炉管中通入氧气和氮气，其中，氧气流量为1-1.5L/min(可选1L/min)，氮气流量为3-3.5L/min(可选3L/min)，炉管压力为150-170mbar(可选160mbar)，时长为5-7min(可选5min)；
(4)保持恒温770-790℃(可选770℃)，混合氧气、大氮和携带POCl 3源的小氮从炉尾进气，其中，小氮流量为1.2-1.5L/min(可选1.2L/min)，氧气 流量为0.8-1L/min(可选0.8L/min)，大氮流量为3-3.5L/min(可选3L/min)，炉管压力为150-170mbar(可选160mbar)，时长为12-15min(可选12min)；
本实施例中，第1，2号舟对应第一温区，将第一温区的温度调整为795℃。第3号舟对应第二温区，将第二温区的温度调整为780℃。
第一温区，第二温区是第1，2，3小舟所对应的热场的位置。
(5)由770-790℃(可选770℃)斜率升温至800-1000℃(可选845℃)，时长为10min，升温过程中通入氧气和氮气；其中，氧气流量为1-1.5L/min(可选1L/min)，氮气流量为3-3.5L/min(可选3L/min)，炉管压力为160mbar；
(6)保持恒温800-1000℃(可选845℃)，时长为10min，在恒温的过程中，补充氮气，氮气流量为3-3.5L/min(可选3L/min)，炉管压力为160mbar；
(7)降温至800度以下，通氮气回到常压，将载有硅片的舟送出炉。
本实施例中采用的进气方式示意图如图2所示，其中，1表示尾部匀流板(相关技术中的匀流板，板面设有小孔)，2表示炉管，3表示热场，4表示炉口隔热板，5表示炉门，6表示桨，7表示尾排管，8表示进气管，9表示补气管。
从炉口至炉尾依次取8个舟中的硅片，每个舟从上到下，等间距取5片，每片测试5处方阻，计算5片中25个测量点的极差。硅片尺寸182mmx182mm，目标方阻160欧姆每方块(Ω/□)的对比方阻、极差数值如下表1所示。
表1
Figure PCTCN2022131310-appb-000001
实施例2
本实施例在实施例1的基础上，将原来的匀流板拆除，在炉尾增加匀流装置，N 2，O 2，POCl 3等气体通过匀流装置进入炉管；使得气体进入炉管后被均匀打散，避免气流直接对硅片进行冲击。可选地，将匀流装置放置于炉管内部，匀流装置距离炉尾部进气管端部10-15cm。
本实施例中，匀流装置可以采用实施例1a中所述的匀流桶，匀流桶距离炉尾部进气管端部10cm，匀流桶如图3-4所示，采用桶状设计。
本实施例中，在使用匀流桶时，让气体先通过封闭面上的开孔3a,再经过桶体流出。在其他实施方式中，也可以先让气体通过桶体1a，再从开孔3a流出。在其他实施方式中，可以采用其他结构的匀流装置。
本实例中其余的步骤与实例1中相同。
同样的取片方式，测算的方阻极差如表2所示。
表2
Figure PCTCN2022131310-appb-000002
实施例3
本实施例在实施例2的基础上，增加补气管，补气管从炉尾插入伸向炉口。本实施例中采用的是石英补气管，补气管靠近炉口的一端封闭，补气管远离炉口的一端开口，用于通入气体，补气管上设有气体出口。在一实施例中，补气管中通入的气体为惰性气体和氮气中的至少之一。示例性的，补气管的结构如实施例2a所述，如图6所示，补气管从炉管的炉尾伸入至炉口，炉尾端进气口通气，炉口端口封闭，在炉管内部的补气管设气体出口。
本实施例中，第1号舟靠近炉口隔热板，第2、3、4…8号舟，向炉尾方向依次排列。
在补气管上，分别在对应1号舟沿炉管长度方向1/4，1/2和3/4处开3个孔；对应2号舟沿炉管长度方向分别在1/3和2/3处开2个孔；对应3号舟沿炉管长度方向在1/2处开1个孔；孔径均为1.5mm。
本实施例中，开孔是圆形孔，在其他实施例中，可以将开孔的形状设置成其他形状。
本实施例在实施例1的基础上，将步骤(4)修改为：
(4)保持恒温770度，混合氧气、大氮和携带POCl 3源的小氮从炉尾进气，其中，小氮流量为1.2L/min，氧气流量为0.8L/min，大氮流量为3L/min，炉管压力为160mbar，时长为12min，在补气管中通0.5-2L/min(可选0.95L/min)的氮气，第1，2和3号舟对应第一温区和第二温区的温度相比实施例1提高5度，即，将第一温区的温度调整为800℃，将第二温区的温度调整为785℃。
本实施例中，在通源的情况下才通入氮气(即开启氮气补偿)，其余时间关闭，氮气通入时间和通源时间一致。在其他实施方式中，在补气管中通入惰性气体，比如，氦气。
本实施例中的其余步骤与实施例2相同。
同样的取片方式，测算的方阻极差如下表3。
表3
Figure PCTCN2022131310-appb-000003
实施例4
本实施例在实施例3的基础上，将步骤(4)修改为:
(4)保持恒温770度，混合氧气、大氮和携带POCl 3源的小氮从炉尾进气，小氮流量为1.2L/min，氧气流量为0.8L/min，大氮流量为3L/min，炉管压力为160mbar，时长为12min，在补气管中通0.5L/min的氮气，第1，2，3号舟对应第一温区和第二温区的温度相比实施例1提高3度，即，将第一温区的温度调整为798℃，将第二温区的温度调整为783℃。
本实施例中的其余步骤与实施例1相同。
同样的取片方式，测算的方阻极差数据见表4。
表4
Figure PCTCN2022131310-appb-000004
实施例5
本实施例在实施例1的基础上，将步骤(4)修改为：
(4)保持恒温770度，混合氧气、大氮和携带POCl 3源的小氮从炉尾进气，小氮流量为1.2L/min，氧气流量为0.8L/min，大氮流量为3L/min，炉管压力为160mbar，时长为12min，在补气管中通2L/min的氮气，第1，2，3号舟对应第一温区和第二温区的温度相比实施例1提高9度，即，将第一温区的温度调整为804℃，将第二温区的温度调整为789℃。
本实施例中的其余步骤与实施例1相同。
测算的方阻极差数据见表5。
表5
Figure PCTCN2022131310-appb-000005
实施例1a
如图3-4所示，本实施例提供一种匀流装置，该匀流装置采用桶状结构，包括桶体1a，桶体1a的第一端开口(此为第一开口7a)，桶体1a的第二端连接封闭面(即将桶体第二端封闭)，封闭面2a上设有开孔3a。桶体1a能够将进入 匀流装置的气体集中起来，避免气体向四周扩散；气体从封闭面2a上的开孔3a流出，被均匀打散，避免气流直接对硅片进行冲击，能够改善改善炉尾上中下硅片方阻的片间差异。
在一些可选的方式中，开孔3a的形状可以为圆形、椭圆、方形、三角形等形状。开孔的数量也可以根据实际需要进行设置。本实施例中，开孔形状为圆形。
在一些可选的方式中，如图3-4所示，匀流装置下部设有支撑件4a，支撑件4a与桶体1a固定连接，支撑件4a能够支撑整个匀流装置，同时支撑件4a可以用于将匀流装置稳定放置在某一位置，比如可以将匀流装置放置在炉管内部。在一些可选的方式中，支撑件4a的形状与炉管内部放置区域的形状相匹配，有利于将匀流装置稳定放置于炉管内部。
在一些可选的方式中，所述支撑件4a为圆柱形，圆柱形的支撑件4a与圆形炉管接触部位相匹配。本实施例中，如图3-4所示，匀流装置包括两个圆柱形的支撑件4a。
在一些可选的方式中，如图3所示，支撑件4a内部中空，并且支撑件4a的第一端开口(此为第二开口8a)，可以将支撑件4a套在相对应的固定件6a上，如图3-4所示，支撑件4a的开口方向与桶体1a的开口方向相反，匀流装置被放置在炉管内部，支撑件4a套在炉管内部的固定件上。因为支撑件4a内部中空，这样还可以减轻整个匀流桶的重量。图5中显示出了一种匀流装置的安装方式，支撑件套在固定件6a上，实现匀流装置与炉管的连接。在其他实施方式中，可以采用其他方式进行安装，比如类似于卡扣形式的安装，炉管内设有卡槽，能够与支撑件配合，实现匀流装置与炉管的连接。
本申请中的匀流装置，在使用时，可以让气体先通过封闭面的开孔3a,再经过桶体流出；也可以先让气体通过桶体1a，再从开孔3a流出。
在一些可选的方式中，如图4所示，匀流装置还包括连接件5a，连接件5a连接支撑件4a，连接件5a配置为能够用于使用者抓握，而且连接件5a与支撑件4a连接在一起，使得整个结构较为稳定。连接件5a可以为多种形状，比如可以是方形连接件、拱形连接件、横向连接件等中的任意一种或者几种形状的结合。
本实施例，连接件5a的形状类似于拱形拉手，如图4所示，连接件5a的两端分别连接两个圆柱形支撑件4a的第二端，连接件5a便于使用者抓握，有利于向炉管中拿取或者放置匀流装置，同时，连接件5a位于桶体1a开口这一侧，可以平衡整个装置的重量分布，使得整个结构较为稳定。
在一些可选的方式中，将匀流装置放置在炉管进气端，匀流装置距离进气端部10-15cm，这样可以增大气体与匀流桶的接触面积，更好的分散气流。
在一些可选的方式中，如图3所示，封闭面2a不是整个面都设有开孔3a，开孔3a区域的形状与小舟形状对应(根据小舟的形状设置)，有利于气体更集中的去往小舟而不是从小舟边上流走。这种桶状的匀流装置在炉管内的稳定性更好，不会晃动，且匀流装置包括连接件5a，便于将匀流装置放进炉管和从炉管中拿出来。
实施例2a
在一些可选的方式中，如图6所示，所述进气结构还包括补气管，补气管被配置为能够补充气体，所述气体可以是氮气和惰性气体中的至少一种，本实施例中，补气管主要用于补充氮气。
在一些可选的方式中，补气管采用堵头的形式，补气管从炉尾插入炉管，伸向炉口；补气管靠近炉口的一端封闭，补气管远离炉口的一端开口(此为第三开口9a)被设置为通入气体。在一些可选的方式中，补气管上设有气体出口10a。在补气管上开设气体出口，出气位置可以为方阻较低的区域，通过增加局部氮气稀释磷源或者硼源的浓度，从而达到提升方阻的效果。
本实施例中，如图6所示，气体出口10a位于补气管的正上方，气体出口10a形状为直径1.5mm的圆孔，在其他实施方式中，气体出口10a可以不位于补气管的正上方，可以是位于补气管的斜上方或者其他方位，气体出口10a的具体位置可以根据实际的需要进行设置。
本申请中，气体出口10a的形状可以为方形、椭圆形等。
本实施例中，如图6所示，气体出口10a位置在进气管的正上方，气体出口形状为直径1.5mm的圆孔，气体出口10a数量为6个，为3，2，1的组合。靠近炉口第一号舟下方是3个孔，第二号小舟下方是2个孔，第三号小舟下方是1个孔，补气管从匀流装置的下方穿过，伸至炉口小舟下方。
在一些可选的方式中，补气管直径为12mm。在其他实施方式中，补气管直径可以是其他数值，可以根据具体需求进行设置。
在一些可选的方式中，在通源步骤，可以增加补气管，通入氮气；在一些实施例中，在通源步设置氮气补偿流量为0.5-2L/min。
本申请中的进气结构可以用于磷扩散，也可以用于硼扩散。
由表中数据可知，实施例3的方阻极差为最小。本申请方法在硅片尺寸182mmx182mm，目标方阻160Ω/□的条件下，通过补充氮气将炉口靠近抽气口 (抽气口即尾排管的进气口)的掺杂源浓度稀释降低，也将气流混合，并向上推送，降低了抽气口对此处的影响，减少了浓度差异，从而降低了硅片方阻极差。在炉尾部增加匀流装置，例如匀流桶，将气流充分打散以后，尽可能多的流向小舟内部，对靠近炉尾几个舟的极差改善较大。在大尺寸硅片、高方阻、高效率电池工艺的前提下，硅片方阻的均匀性要求越来越高，相关技术中扩散工艺的问题逐渐显露出来，需要多方共同改善提高工艺质量。
本申请通过将靠近抽气口(尾排管在炉管中的一端)的硅片处增加补气，解决了近抽气口处硅片方阻的不均匀性，降低了方阻极差。相关方式，需要舍弃近抽气口处的部分硅片，减少单管硅片装载量来获得整管的均匀性。本申请，可以直接将近抽气口的硅片方阻极差改善，使得硅片均匀性达到合格区域内，且提高了产能。
如图1所示，相关进气方式，炉口气流偏向尾排口，导致炉口下部分硅片处气流较大，由于掺杂气体密度一般都较大，在混合气体中下沉，导致炉口下部分气体浓度大，流量大，从而导致下部分硅片方阻偏小，硅片方阻极差变大。相关方式调节炉管压力，改善气流比例，以及改变炉口硅片处的温度来改善炉口处硅片的方阻异常。炉口进气，炉尾抽气的方式同样存在类似问题。此类相关调整能略微减小差异，但要保持其他位置硅片的稳定，改善有限。通常减少出气口处的硅片数量来达到整管硅片的一致性。
本申请在炉口处增加一氮气管道，在底部充氮气，如图2所示，不仅能够稀释出气口处的高浓度掺杂气体，还可以将此处的气流向上推动混合均匀，降低尾排管对此处的抽力。同时配合此处热场温度的调整(通过调节第一温区、第二温区的温度调整小舟的方阻)，能够获得方阻极差小的硅片。
本申请的有益效果是：
(1)在炉管进气端增加匀流装置，使得气体进入炉管后被均匀打散，避免气流直接对硅片进行冲击，改善了炉尾上中下的片间差异。本申请通源时在近出气口处补充氮气，稀释掺杂源，将气体混合并推动，改善了局部掺杂源的浓度差异，提高了硅片方阻均匀性，可以在不改变相关排气结构的情况下改善排气管进口位置片间的均匀性，且对其他舟内的方阻无影响，可实现单独调控区域方阻。
(2)本申请提供的扩散方法，能够提高扩散方阻均匀性，减少方阻极差，增加设备产能。
(3)本申请通过对炉口均匀性的改善可以使得产能及硅片均匀性都得到提 升，不需要增加炉管长度，使硅片远离气流不稳定区域，节省了机台空间与机台制造成本。
(4)本申请中，匀流装置的封闭面不是整个面都设有开孔，开孔区域的形状与小舟形状对应(可以根据小舟的形状设置)，有利于气体更集中的去往小舟而不是从小舟边上流走。这种桶状的匀流装置在炉管内的稳定性更好，不会晃动，且增加了连接件，便于放进炉管和从炉管中拿出来。
(5)本申请中，采用补气管，可以用于补充氮气，可以在不改变相关抽气结构的情况下改善抽气口位置片间的均匀性，且几乎对其他舟内的方阻无影响，可实现单独调空区域方阻。扩散后方阻的均匀性较好有利于后续工艺的匹配，整体电性能也更加稳定。

Claims (8)

  1. 一种气体扩散方法，包括：
    将载有硅片的舟送入炉管中，将匀流装置放置于炉管内部，匀流装置靠近炉尾部；
    对炉管抽真空并检漏；
    将炉管升温至770-790℃后，往炉管通入氧气和氮气，炉管压力为150-170mbar；
    保持恒温770-790℃，将混合氧气、大氮和携带POCl 3源的小氮从炉尾进气，炉管压力为150-170mbar；
    由770℃-790℃斜率升温至800-1000℃，时长为5-20min，升温过程中通入氧气和氮气，炉管压力为150-170mbar；
    保持恒温800-1000℃，时长为5-20min，在恒温的过程中，补充氮气，炉管压力为150-170mbar；
    降温，通氮气回到常压，将载有硅片的舟送出炉。
  2. 根据权利要求1所述的气体扩散方法，其中，所述将混合氧气、大氮和携带POCl3源的小氮从炉尾进气，包括，补气管从炉尾插入炉管，伸向炉口；
    补气管靠近炉口的一端封闭，补气管远离炉口的一端开口，用于通入气体，补气管上设有气体出口；
    补气管中通入的气体为惰性气体和氮气中的至少之一。
  3. 根据权利要求1所述的气体扩散方法，其中，所述将混合氧气、大氮和携带POCl 3源的小氮从炉尾进气时，小氮流量为1.2-1.5L/min，氧气流量为0.8-1L/min，大氮流量为3-3.5L/min，通入时长为12-15min。
  4. 根据权利要求1所述的气体扩散方法，其中，所述将炉管升温至770-790℃后，往炉管通入氧气和氮气时，氧气流量为1-1.5L/min，氮气流量为3-3.5L/min，通入时长为5-7min。
  5. 根据权利要求2所述的气体扩散方法，其中，所述将混合氧气、大氮和携带POCl 3源的小氮从炉尾进气时，补气管中通入氮气的流量为0.5-2L/min。
  6. 根据权利要求1所述的气体扩散方法，其中，所述由770-790℃斜率升温至800-1000℃，升温过程中通入氧气和氮气时，氧气流量为1-1.5L/min，氮气流量为3-3.5L/min。
  7. 根据权利要求1所述的气体扩散方法，其中，所述保持恒温800-1000℃，补充氮气时，氮气流量为3-3.5L/min。
  8. 根据权利要求1所述的气体扩散方法，其中，所述降温，包括：降温至800℃以下。
PCT/CN2022/131310 2021-11-17 2022-11-11 一种气体扩散方法 WO2023088173A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202111359969.4 2021-11-17
CN202111359969.4A CN114171377A (zh) 2021-11-17 2021-11-17 一种新型扩散方法

Publications (1)

Publication Number Publication Date
WO2023088173A1 true WO2023088173A1 (zh) 2023-05-25

Family

ID=80479827

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/131310 WO2023088173A1 (zh) 2021-11-17 2022-11-11 一种气体扩散方法

Country Status (2)

Country Link
CN (1) CN114171377A (zh)
WO (1) WO2023088173A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117089825A (zh) * 2023-06-01 2023-11-21 无锡松煜科技有限公司 一种流体分布均匀的镀覆腔室及镀覆方法
CN117438277A (zh) * 2023-12-19 2024-01-23 北京北方华创微电子装备有限公司 匀流组件、进气装置及半导体设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114171377A (zh) * 2021-11-17 2022-03-11 深圳市拉普拉斯能源技术有限公司 一种新型扩散方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102820383A (zh) * 2012-09-11 2012-12-12 江阴鑫辉太阳能有限公司 多晶硅太阳能电池扩散方法
CN103346074A (zh) * 2013-07-12 2013-10-09 九州方园新能源股份有限公司 一种采用多步梯度扩散法制备晶体硅电池片的方法
CN107507887A (zh) * 2017-08-25 2017-12-22 苏州阿特斯阳光电力科技有限公司 一种控制掺杂曲线一致性的方法
CN107785458A (zh) * 2017-10-16 2018-03-09 浙江昱辉阳光能源江苏有限公司 一种实现深结低表面浓度的晶体硅扩散工艺
CN214254438U (zh) * 2020-12-31 2021-09-21 深圳市拉普拉斯能源技术有限公司 一种硼扩散设备
CN114171377A (zh) * 2021-11-17 2022-03-11 深圳市拉普拉斯能源技术有限公司 一种新型扩散方法
CN217387086U (zh) * 2021-11-17 2022-09-06 深圳市拉普拉斯能源技术有限公司 一种进气结构

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102820383A (zh) * 2012-09-11 2012-12-12 江阴鑫辉太阳能有限公司 多晶硅太阳能电池扩散方法
CN103346074A (zh) * 2013-07-12 2013-10-09 九州方园新能源股份有限公司 一种采用多步梯度扩散法制备晶体硅电池片的方法
CN107507887A (zh) * 2017-08-25 2017-12-22 苏州阿特斯阳光电力科技有限公司 一种控制掺杂曲线一致性的方法
CN107785458A (zh) * 2017-10-16 2018-03-09 浙江昱辉阳光能源江苏有限公司 一种实现深结低表面浓度的晶体硅扩散工艺
CN214254438U (zh) * 2020-12-31 2021-09-21 深圳市拉普拉斯能源技术有限公司 一种硼扩散设备
CN114171377A (zh) * 2021-11-17 2022-03-11 深圳市拉普拉斯能源技术有限公司 一种新型扩散方法
CN217387086U (zh) * 2021-11-17 2022-09-06 深圳市拉普拉斯能源技术有限公司 一种进气结构

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117089825A (zh) * 2023-06-01 2023-11-21 无锡松煜科技有限公司 一种流体分布均匀的镀覆腔室及镀覆方法
CN117438277A (zh) * 2023-12-19 2024-01-23 北京北方华创微电子装备有限公司 匀流组件、进气装置及半导体设备
CN117438277B (zh) * 2023-12-19 2024-04-12 北京北方华创微电子装备有限公司 匀流组件、进气装置及半导体设备

Also Published As

Publication number Publication date
CN114171377A (zh) 2022-03-11

Similar Documents

Publication Publication Date Title
WO2023088173A1 (zh) 一种气体扩散方法
CN105261670B (zh) 晶体硅电池的低压扩散工艺
CN104393107B (zh) 一种高方阻晶体硅电池低压扩散工艺
CN102820383B (zh) 多晶硅太阳能电池扩散方法
CN100530704C (zh) 一种应用于硅太阳能电池的扩散工艺
CN106856215B (zh) 太阳能电池片扩散方法
CN102005502B (zh) 一种改善太阳能电池磷扩散均匀性的方法
CN104409339B (zh) 一种硅片的p扩散方法和太阳能电池的制备方法
CN104269459A (zh) 一种制备高方阻电池片的减压扩散工艺
CN105140347B (zh) 快速改善p型晶硅电池光致衰减的量产装置及其使用方法
CN105780127B (zh) 一种晶体硅太阳能电池的磷扩散方法
CN214254438U (zh) 一种硼扩散设备
CN109713084A (zh) 一种改善太阳能电池扩散工艺中方阻均匀性的方法
CN101494253B (zh) 一种选择性发射极太阳电池制造过程中的重扩散和轻扩散工艺
CN217387086U (zh) 一种进气结构
CN201713608U (zh) 太阳能电池硅片扩散炉
CN109371471B (zh) 双层外延片的生长方法及双层外延片
CN107946402A (zh) 太阳能电池片扩散方法
CN204668282U (zh) 一种高温低压扩散装置
CN112144117B (zh) 氢、磷、氮掺杂单晶硅及其制备方法、太阳能电池
CN102094247A (zh) 磷扩散炉管两端进气装置
CN104752564A (zh) 一种提高多晶硅开路电压的新型扩散工艺
CN219824435U (zh) 一种扩散炉
CN107785458A (zh) 一种实现深结低表面浓度的晶体硅扩散工艺
CN106024599B (zh) 太阳能电池片的扩散工艺

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22894710

Country of ref document: EP

Kind code of ref document: A1