WO2022213460A1 - 一种集成隧穿氧化层的非晶硅制备方法 - Google Patents

一种集成隧穿氧化层的非晶硅制备方法 Download PDF

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WO2022213460A1
WO2022213460A1 PCT/CN2021/096255 CN2021096255W WO2022213460A1 WO 2022213460 A1 WO2022213460 A1 WO 2022213460A1 CN 2021096255 W CN2021096255 W CN 2021096255W WO 2022213460 A1 WO2022213460 A1 WO 2022213460A1
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amorphous silicon
oxide layer
boat
furnace tube
tunnel oxide
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French (fr)
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欧文凯
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普乐新能源科技(徐州)有限公司
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Publication of WO2022213460A1 publication Critical patent/WO2022213460A1/zh
Priority to US18/446,505 priority patent/US20230395377A1/en

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Definitions

  • the invention belongs to the technical field of solar cells, and particularly relates to a method for preparing amorphous silicon with an integrated tunnel oxide layer.
  • a conventional way to solve this influencing factor is to use local contact.
  • This structure reduces the effective contact area between the silicon base and the metal electrode, and the uncontacted area is blocked by passivation layers or other masking layers, such as PERC, PERL and other battery structures. .
  • passivation layers or other masking layers such as PERC, PERL and other battery structures.
  • Another option to reduce contact recombination is to use selectively passivated contacts, a structure consisting of a material placed between a silicon base and a metal electrode, which effectively inhibits the recombination of charge carriers through defects at the silicon surface. At the same time, it also plays a role in contact. Since the recombination loss of this passivation contact is very low, it can be used as a passivation layer on the whole surface, avoiding the use of a separate passivation layer and local metal contact. Selectively passivated contact structures have the potential to simplify the solar cell fabrication process and increase efficiency.
  • N-TOPCon cells are based on the theory of selective contact passivation, and the structure includes an ultra-thin oxide layer (electron tunneling layer) and a phosphorus-doped polysilicon layer (SiOx/doped-poly Si).
  • TOPCon batteries have different process routes due to different equipment and processes.
  • the difficulty of the industrialized TOPCon process lies in the balance of yield, production capacity, efficiency and cost. Whether the factory can gain advantages in technology and cost in the future, the formulation of the process route is particularly important.
  • the present invention provides a method for preparing amorphous silicon with an integrated tunnel oxide layer.
  • the present invention provides the following technical solutions:
  • a method for preparing amorphous silicon with an integrated tunnel oxide layer comprising the following steps:
  • Oxidation keep the pressure stable, and after heating until the furnace tube temperature is stable, oxygen is introduced to carry out SiO2 growth; the stable temperature range is 550-620 °C, the flow rate of O2 is in the range of 5-30slm, and the time is 5-30 minute;
  • Amorphous silicon growth After the temperature and pressure are stabilized, SiH 4 is introduced to grow amorphous silicon; the stable temperature range is 550-600 ° C, the flow rate of SiH 4 is 80-1000 sccm, the pressure range is 250-600 mtorr, and the time is 10 ⁇ 150 minutes;
  • step (1) the internal temperature of the furnace tube is 450-600° C., and the N 2 flow range is 1-30 slm.
  • step (2) the stable temperature range is 560-600°C.
  • step (2) the O 2 flow range is 10-20 slm, and the time is 8-15 minutes.
  • step (3) vacuum is applied to make the furnace tube atmosphere less than 100 mtorr.
  • step (4) the N 2 flow range is 100-10000 sccm, the back pressure pressure is 250-1000 mtorr, and the holding time is 0.5-10 min.
  • step (4) the N 2 flow range is 200-1000 sccm, the back pressure pressure is 250-600 mtorr, and the holding time is 0.5-5 min.
  • the SiH 4 flow range is 200-500 sccm
  • the pressure is 300-500 mtorr
  • the time is 20-60 minutes.
  • step (7) the cooling temperature range is 400-550°C.
  • the present invention uses a method of growing amorphous silicon with an integrated ultra-thin oxide layer, that is, the growth of the ultra-thin tunnel oxide layer and the growth of amorphous silicon are performed in the same process, and there is no Q-time time, which can reduce the process steps.
  • the present invention uses an amorphous silicon growth method with an integrated ultra-thin oxide layer, which does not involve additional loading and unloading processes, does not increase the risk of scratches and contamination, and is more excellent than the separate method of oxidation and amorphous silicon growth. passivation results.
  • FIG. 1 is a flow chart of a method for preparing amorphous silicon with an integrated tunnel oxide layer according to the present invention.
  • a and/or B can mean that A exists alone, A and B exist at the same time, and B exists alone.
  • the terms “first”, “second”, “third”, etc. involved in this application are only to distinguish similar objects, and do not represent a specific order for the objects.
  • a method for preparing amorphous silicon with an integrated tunnel oxide layer comprising the following steps:
  • Oxidation keep the pressure stable, heat to the furnace tube temperature of 560 ° C, after the temperature is stable, feed oxygen to carry out SiO 2 growth; O 2 flow range 10slm, time 10 minutes;
  • Amorphous silicon growth after the temperature and pressure are stabilized, SiH 4 is introduced to conduct amorphous silicon growth; SiH 4 flow range is 200sccm, pressure is 300mtorr, and time is 40 minutes;
  • Cooling and releasing the boat after the temperature is lowered, the boat is taken out from the furnace tube after breaking the vacuum, and the cooling temperature range is 400 °C;
  • a method for preparing amorphous silicon with an integrated tunnel oxide layer comprising the following steps:
  • SiH 4 is introduced to conduct amorphous silicon growth; SiH 4 flow range is 1000sccm, pressure 400mtorr, and time 10 minutes;
  • Cooling and releasing the boat after the temperature is lowered, the boat is taken out from the furnace tube after breaking the vacuum, and the cooling temperature range is 450°C;
  • a method for preparing amorphous silicon with an integrated tunnel oxide layer comprising the following steps:
  • Oxidation keep the pressure stable, after heating until the furnace tube temperature is stable, oxygen is introduced to carry out SiO2 growth; the stable temperature range is 600°C, the O2 flow range is 15slm, and the time is 15 minutes;
  • Amorphous silicon growth after the temperature and pressure are stabilized, SiH 4 is introduced to grow amorphous silicon; the flow range of SiH 4 is 500sccm, the pressure is 500mtorr, and the time is 30 minutes;
  • Cooling and releasing the boat after the temperature is lowered, the boat is taken out from the furnace tube after breaking the vacuum, and the cooling temperature range is 550°C;
  • a method for preparing amorphous silicon with an integrated tunnel oxide layer comprising the following steps:
  • Oxidation keep the pressure stable, and after heating until the furnace tube temperature is stable, oxygen is introduced to carry out SiO2 growth; the stable temperature range is 550°C, the O2 flow range is 5slm, and the time is 30 minutes;
  • Amorphous silicon growth after the temperature and pressure are stabilized, SiH 4 is introduced to conduct amorphous silicon growth; SiH 4 flow range is 80sccm, pressure is 250mtorr, and time is 150 minutes;
  • Cooling and releasing the boat after the temperature is lowered, the boat is taken out from the furnace tube after breaking the vacuum, and the cooling temperature range is 400 °C;
  • Contact quality in crystalline silicon cells can be characterized by J0 and PL values.
  • the monitor film is an N-type polished film. After the oxidation and amorphous silicon processes are completed on the back side (using the method for preparing amorphous silicon with an integrated tunnel oxide layer as described in Example 1 above), double-sided phosphorous expansion is performed, and a cleaning machine is used to remove it. After double-sided PSG, double-sided SiNx film was plated. Finally, after sintering, WCT120 and PL machines were used to test J 0 and PL values.
  • a single crystal silicon wafer (CZ Si) prepared by a single-throw N-type Czochralski method with a thickness of 1.175 ⁇ m and a resistivity of 1 to 3 ⁇ cm.
  • the reflectivity of the treated silicon wafer is about 30-40%;
  • the silicon wafer is put into the phosphorus diffusion equipment for phosphorus doping treatment.
  • the conventional phosphorus doping method in the prior art is adopted, and the phosphorus doping temperature is 790° C.
  • the source is POCl3, the gas source volume is 800-1000sccm, and the passage time is 20-25min;
  • the above is the preparation method of the amorphous silicon process monitoring sheet with integrated tunnel oxide layer, in which, except for the preparation method of amorphous silicon integrated with tunnel oxide layer of the present invention, other processing methods are conventional in the prior art .
  • step (3) the conventional method is used to carry out the tunneling oxide layer and the growth of amorphous silicon, and after the tunneling oxide layer is completed After the growth of the silicon wafer, the temperature of the silicon wafer is cooled, and then the growth of amorphous silicon is carried out.
  • the normal pressure oxidation process is usually used in the conventional process. The oxidation under normal pressure usually has a fast growth rate, poor controllability, and is greatly affected by the environment.
  • Vacuum degree keep the vacuum degree at 100-700 Torr, reduce the growth rate of the oxide layer, and at the same time, it is less affected by environmental cleanliness under vacuum, and can obtain a high-quality thin oxide layer.
  • the conventional oxidation process flow is: chip loading (oxidation furnace tube carrier) - tube inlet - heating - oxygen oxidation (atmospheric pressure) - cooling - tube cooling - unloading - chip loading (amorphous silicon furnace tube carrier) - The process of entering the tube - heating up and vacuuming - growing amorphous silicon - cooling down and breaking the vacuum - exiting the tube and cooling - unloading is complicated, and the carrier needs to be switched.
  • Tables 1 and 2 are the passivation results of the monitor wafers prepared by the integrated and non-integrated processes, respectively.
  • Table 1 Table of passivation results of amorphous silicon with integrated oxide layer
  • Table 2 Table of passivation results prepared by oxide layer and amorphous silicon layer respectively
  • the sample prepared by the method of the present invention has a longer minority carrier lifetime, a smaller current density value, a larger filling factor, a larger open circuit voltage, and different furnace tubes.
  • the difference of the test data of the position monitoring sheet is small, which shows that the sample prepared by the method of the present invention has good uniformity.
  • the sample prepared by the method of the invention can be tested with a minority carrier lifetime of more than 2000 ⁇ s, indicating that it has good passivation performance; and the higher the minority carrier lifetime, the smaller the recombination, and the higher the battery efficiency.
  • amorphous silicon passivation result of the integrated oxide layer of the present invention is better than the passivation result of the oxide layer and the amorphous silicon prepared separately.

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Abstract

本发明公开了一种集成隧穿氧化层的非晶硅制备方法，即超薄隧穿氧化层与非晶硅的生长在同一工序进行，无Q-time时间，可减少工艺步骤，不涉及额外的上下片过程，不会增加划伤及污染风险，比氧化与非晶硅生长分开方式拥有更优异的钝化结果。

Description

一种集成隧穿氧化层的非晶硅制备方法 技术领域
本发明属于太阳能电池技术领域，具体涉及一种集成隧穿氧化层的非晶硅制备方法。
背景技术
光伏发电要想成为普惠能源，必须首先实现平价上网。因此要进一步提高太阳能电池的转换效率，减少度电成本。接触区的复合损失是限制工业太阳能电池效率提升的非常重要的因素。
解决这个影响因素的一种常规方式是采用局部接触，这种结构使硅基与金属电极的有效接触面积减少，未接触的区域被钝化层或者其他掩蔽层阻隔，如PERC、PERL等电池结构。然而，这种电池结构的载流子横向传输带来的欧姆损失是电池设计的关键。
另一种减少接触复合的方案是采用选择性钝化接触方式，这种结构由置于硅基和金属电极之间的材料组成，有效地抑制电荷载流子通过硅表面处的缺陷重新复合，同时又起到接触的作用。由于这种钝化接触的复合损失很低，可以作为整面的钝化层，避免使用单独的钝化层和局部金属接触。选择性钝化接触结构具备简化太阳能电池制造流程和高效率的潜力。N-TOPCon电池基于选择性接触钝化理论，结构中包含超薄氧化层(电子隧穿层)和磷掺杂的多晶硅层(SiOx/doped-poly Si)。
TOPCon电池因所用设备和工艺不同，工艺路线也有所差别。工业化TOPCon工艺难点在于良率、产能、效率与成本的平衡，工厂在未来能否在技术和成本上取得优势，工艺路线的制定尤为重要。
发明内容
针对上述情况，为克服现有技术的缺陷，本发明提供一种集成隧穿氧化层的非晶硅制备方法。
为了实现上述目的，本发明提供以下技术方案：
一种集成隧穿氧化层的非晶硅制备方法，包括以下步骤：
(1)进舟：将完成表面抛光的硅片装入舟中，将舟推进入炉管中，进舟过程中通入N 2；进舟完成后，停止通入N 2，对炉管进行抽真空处理，保持真空度 在100-700Torr；
(2)氧化：保持压力稳定，加热至炉管温度稳定后，通入氧气，进行SiO 2生长；稳定温度范围为550-620℃，通入O 2流量范围5-30slm，时间为5～30分钟；
(3)抽真空：完成氧化后，打开阀抽真空，使炉管氛围为1000mtorr以下状态；
(4)回压：通入N 2回压，保持一段时间；
(5)非晶硅生长：温度压力稳定后，通入SiH 4，进行非晶硅生长；稳定温度范围550-600℃，通入SiH 4流量范围80～1000sccm，压力范围250～600mtorr，时间10～150分钟；
(6)通入N 2，排出管内剩余SiH 4；
(7)降温出舟：温度降低后，破真空后将舟从炉管中取出；
(8)卸片：将硅片从舟上取下。
进一步地，步骤(1)中，炉管内部温度为450～600℃，N 2流量范围1～30slm。
进一步地，步骤(2)中，稳定温度范围560～600℃。
进一步地，步骤(2)中，O 2流量范围10～20slm，时间8～15分钟。
进一步地，步骤(3)中，抽真空，使炉管氛围为小于100mtorr状态。
进一步地，步骤(4)中，N 2流量范围100～10000sccm，回压压力范围250～1000mtorr，保持时间0.5～10min。
进一步地，步骤(4)中，N 2流量范围200～1000sccm，回压压力范围250～600mtorr，保持时间0.5～5min。
进一步地，步骤(5)中，SiH 4流量范围200～500sccm，压力300～500mtorr，时间20～60分钟。
进一步地，步骤(7)中，降温温度范围400～550℃。
本发明的有益效果是：
(1)本发明使用一种集成超薄氧化层的非晶硅生长的方式，即超薄隧穿氧化层与非晶硅的生长在同一工序进行，无Q-time时间，可减少工艺步骤。
(2)本发明使用一种集成超薄氧化层的非晶硅生长的方式，不涉及额外的上下片过程，不会增加划伤及污染风险，比氧化与非晶硅生长分开方式拥有更优 异的钝化结果。
附图说明
图1是本发明集成隧穿氧化层的非晶硅制备方法的流程图。
具体实施方式
为了使本申请的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本申请进行描述和说明。应当理解，此处所描述的具体实施例仅仅用以解释本申请，并不用于限定本申请。基于本申请提供的实施例，本领域普通技术人员在没有作出创造性劳动的前提下所获得的所有其他实施例，都属于本申请保护的范围。
在本申请中提及“实施例”意味着，结合实施例描述的特定特征、结构或特性可以包含在本申请的至少一个实施例中。本领域普通技术人员显式地和隐式地理解的是，本申请所描述的实施例在不冲突的情况下，可以与其它实施例相结合。
除非另作定义，本申请所涉及的技术术语或者科学术语应当为本申请所属技术领域内具有一般技能的人士所理解的通常意义。本申请所涉及的“一”、“一个”、“一种”、“该”等类似词语并不表示数量限制，可表示单数或复数。本申请所涉及的术语“包括”、“包含”、“具有”以及它们任何变形，意图在于覆盖不排他的包含；本申请所涉及的“连接”、“相连”、“耦接”等类似的词语并非限定于物理的或者机械的连接，而是可以包括电气的连接，不管是直接的还是间接的。本申请所涉及的“多个”是指大于或者等于两个。“和/或”描述关联对象的关联关系，表示可以存在三种关系，例如，“A和/或B”可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。本申请所涉及的术语“第一”、“第二”、“第三”等仅仅是区别类似的对象，不代表针对对象的特定排序。
实施例1
一种集成隧穿氧化层的非晶硅制备方法，包括以下步骤：
(1)进舟：将完成表面抛光的硅片装入舟中，将舟推进入炉管中，进舟过程中通入N 2，炉管内部温度范围450℃，N 2流量范围1～30slm，形成炉管内正压，防止外部颗粒进入炉体，造成污染。进舟完成后，停止通入N 2，对炉管进行抽真空处理，保持真空度在100Torr稳定。
(2)氧化：保持压力稳定，加热至炉管温度为560℃，温度稳定后，通入 氧气，进行SiO 2生长；O 2流量范围10slm，时间10分钟；
(3)抽真空：完成氧化后，打开阀抽真空，使炉管氛围为100mtorr以下低压状态；
(4)回压：通入N 2回压，保持一段时间；N 2流量范围200sccm，回压压力范围250mtorr，保持时间3min；
(5)非晶硅生长：温度压力稳定后，通入SiH 4，进行非晶硅生长；SiH 4流量范围200sccm，压力300mtorr，时间40分钟；
(6)通入N 2，排出管内剩余SiH 4；
(7)降温出舟：温度降低后，破真空后将舟从炉管中取出，降温温度范围400℃；
(8)卸片：将硅片从石英舟上取下。
实施例2
一种集成隧穿氧化层的非晶硅制备方法，包括以下步骤：
(1)进舟：将完成表面抛光的硅片装入舟中，将舟推进入炉管中，进舟过程中通入N 2，炉管内部温度范围600℃，N 2流量范围20slm，用于排出炉管内空气，形成炉管内正压。进舟完成后，停止通入N 2，对炉管进行抽真空处理，保持真空度在200Torr稳定。
(2)氧化：保持压力稳定，加热至炉管温度稳定后，通入氧气，进行SiO 2生长；稳定温度为620℃，O 2流量范围30slm，时间5分钟；
(3)抽真空：完成氧化后，打开阀抽真空，使炉管氛围为1000mtorr以下低压状态；
(4)回压：通入N 2回压，保持一段时间；N 2流量范围10000sccm，回压压力范围1000mtorr，保持时间1min；
(5)非晶硅生长：温度压力稳定后，通入SiH 4，进行非晶硅生长；SiH 4流量范围1000sccm，压力400mtorr，时间10分钟；
(6)通入N 2，排出管内剩余SiH 4；
(7)降温出舟：温度降低后，破真空后将舟从炉管中取出，降温温度范围450℃；
(8)卸片：将硅片从石英舟上取下。
实施例3
一种集成隧穿氧化层的非晶硅制备方法，包括以下步骤：
(1)进舟：将完成表面抛光的硅片装入舟中，将舟推进入炉管中，进舟过程中通入N 2，炉管内部温度范围500℃，N 2流量范围30slm，用于排出炉管内空气，形成炉管内正压。进舟完成后，停止通入N 2，对炉管进行抽真空处理，保持真空度在500Torr稳定。
(2)氧化：保持压力稳定，加热至炉管温度稳定后，通入氧气，进行SiO 2生长；稳定温度范围600℃，O 2流量范围15slm，时间15分钟；
(3)抽真空：完成氧化后，打开阀抽真空，使炉管氛围为100mtorr以下低压状态；
(4)回压：通入N 2回压，保持一段时间；N 2流量范围1000sccm，回压压力范围600mtorr，保持时间1min；
(5)非晶硅生长：温度压力稳定后，通入SiH 4，进行非晶硅生长；SiH 4流量范围500sccm，压力500mtorr，时间30分钟；
(6)通入N 2，排出管内剩余SiH 4；
(7)降温出舟：温度降低后，破真空后将舟从炉管中取出，降温温度范围550℃；
(8)卸片：将硅片从石英舟上取下。
实施例4
一种集成隧穿氧化层的非晶硅制备方法，包括以下步骤：
(1)进舟：将完成表面抛光的硅片装入舟中，将舟推进入炉管中，进舟过程中通入N 2，炉管内部温度范围450℃，N 2流量范围20slm，用于排出炉管内空气，形成炉管内正压。进舟完成后，停止通入N 2，对炉管进行抽真空处理，保持真空度在700Torr稳定。
(2)氧化：保持压力稳定，加热至炉管温度稳定后，通入氧气，进行SiO 2生长；稳定温度范围550℃，O 2流量范围5slm，时间30分钟；
(3)抽真空：完成氧化后，打开阀抽真空，使炉管氛围为100mtorr以下低压状态；
(4)回压：通入N 2回压，保持一段时间；N 2流量范围100sccm，回压压力 范围250mtorr，保持时间5min；
(5)非晶硅生长：温度压力稳定后，通入SiH 4，进行非晶硅生长；SiH 4流量范围80sccm，压力250mtorr，时间150分钟；
(6)通入N 2，排出管内剩余SiH 4；
(7)降温出舟：温度降低后，破真空后将舟从炉管中取出，降温温度范围400℃；
(8)卸片：将硅片从石英舟上取下。
实施例5
晶硅电池中接触质量可以用J 0和PL值来表征。
监控片使用N型抛光片，背面完成氧化与非晶硅工艺后(采用如上实施例1所述的集成隧穿氧化层的非晶硅制备方法)，进行双面磷扩，使用清洗机台去除双面PSG后双面镀SiNx膜，最后经烧结后分别使用WCT120与PL机台测试J 0及PL值。
具体制作过程如下：
1.175μm厚，电阻率为1～3Ω·cm的单抛N型直拉法制备的单晶硅片(CZ Si)。
2.将硅片放入抛光清洗机，利用HNO 3/HF混合溶液对硅片表面进行抛光处理，处理后的硅片反射率为30-40％左右；
3.将完成抛光处理的硅片放入石英舟，使用本发明的制备方法进行隧穿氧化层及非晶硅生长(具体如实施例1所述)。
4.完成生长后，将硅片放入磷扩散设备，进行磷掺杂处理，本实施例中，采用现有技术中常规的磷掺杂方法，磷掺杂温度为790℃，通入的磷源为POCl3，气源量为800-1000sccm，通入时间长20-25min；
5.磷扩散后放入HF溶液，去除磷扩散后形成的PSG。
6.进入PECVD设备，进行双面SiNx镀膜保护；本实施例中，采用现有技术中常规的SiNx镀膜工艺，本发明不对SiNx镀膜工艺进行改进。
7.将完成镀膜的监控片经过烧结炉700-850℃的烧结后进行J 0及PL值的测试；
如上为所述集成隧穿氧化层的非晶硅工艺监控片的制备方式，其中除了本发 明的集成隧穿氧化层的非晶硅制备方法之外，其他均是现有技术中常规的处理方式。
非集成工艺制备监控片的方法(作为对比)与以上所述的步骤相同，不同点在于：步骤(3)，采用常规的方法进行隧穿氧化层及非晶硅生长，在完成隧穿氧化层的生长后，将硅片降温冷却，再进行非晶硅的生长。而且常规工艺通常使用常压氧化工艺，常压下氧化通常生长速率较快，可控性差，受环境影响较大，对于TOPCON工艺所需生长的超薄隧穿氧化层不利，本发明保持一定的真空度，保持真空度在100-700Torr，降低氧化层生长速率，同时真空下受环境洁净度等影响较小，能够获得质量较高的薄层氧化层，通过钝化数据表征，可以看到明显的提升。常规氧化工艺流程为：装片(氧化炉管载具)-进管-升温-通氧氧化(常压)-降温-出管冷却-卸片-装片(非晶硅炉管载具)-进管-升温抽真空-生长非晶硅-降温破真空-出管冷却-卸片，流程较为复杂，且需要切换载具。
表1与表2分别为集成与非集成工艺制备的监控片的钝化结果。
表1：集成氧化层的非晶硅的钝化结果表
position Lifetime_(μs) Jo_(fA/cm 2) I-Voc_(V) I-FF_(％) PL
1 2314.57 11.96 0.7103 84.8 68894
2 2370.49 10.96 0.7104 85.16 69475
3 2720.07 11.58 0.7116 85.51 69362
4 2245.47 10.77 0.7111 84.26 70013
5 3315.86 10.08 0.7134 86.02 69740
表2：氧化层与非晶硅层分别制备的钝化结果表
position Lifetime_(μs) Jo_(fA/cm 2) I-Voc_(V) I-FF_(％) PL
1 732.24 32.08 0.6846 83.94 58585
2 1449.31 19.98 0.6983 84.96 70892
3 2124.98 14.17 0.7076 85.13 72199
4 869.78 29.46 0.6878 84.31 58662
5 800.79 33.79 0.6858 82.85 47286
注：电流密度J 0，少子寿命Lifetime，开路电压(Open Circuit Voltage,Voc)，填充因子(Fill Factor,FF)，PL为光致发光强度，强度越高表明其钝化能力越强；所述position指的是测试时，从炉管入口至炉尾均匀分布选择监控片，按照1-5编号，目的是为了能够监测炉管内所有区域的生长情况。
由表1-2中数据可知，与非集成工艺制备方法相比，本发明方法制得样品的少子寿命较长，电流密度值较小，填充因子较大，开路电压较大，而且炉管内不同位置监控片的测试数据差别较小，这说明本发明方法制备的样品均匀性好。
利用本发明方法制备的样品经测试少子寿命可达到2000μs以上，说明具备良好的钝化性能；而且少子寿命越高，复合越小，电池效率越高。综上可知，本发明集成氧化层的非晶硅钝化结果优于氧化层与非晶硅分开制备的钝化结果。
本领域的技术人员应该明白，以上所述实施例的各技术特征可以进行任意的组合，为使描述简洁，未对上述实施例中的各个技术特征所有可能的组合都进行描述，然而，只要这些技术特征的组合不存在矛盾，都应当认为是本说明书记载的范围。
以上所述实施例仅表达了本申请的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对发明专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进，这些都属于本申请的保护范围。

Claims (9)

  1. 一种集成隧穿氧化层的非晶硅制备方法，其特征是，包括以下步骤：
    (1)进舟：将完成表面抛光的硅片装入舟中，将舟推进入炉管中，进舟过程中通入N 2；进舟完成后，停止通入N 2，对炉管进行抽真空处理，保持真空度在100-700Torr；
    (2)氧化：保持压力稳定，加热至炉管温度稳定后，通入氧气，进行SiO 2生长；稳定温度范围为550-620℃，通入O 2流量范围5-30slm，时间为5～30分钟；
    (3)抽真空：完成氧化后，打开阀抽真空，使炉管氛围为1000mtorr以下状态；
    (4)回压：通入N 2回压，保持一段时间；
    (5)非晶硅生长：温度压力稳定后，通入SiH 4，进行非晶硅生长；稳定温度范围550-600℃，通入SiH 4流量范围80～1000sccm，压力范围250～600mtorr，时间10～150分钟；
    (6)通入N 2，排出管内剩余SiH 4；
    (7)降温出舟：温度降低后，破真空后将舟从炉管中取出；
    (8)卸片：将硅片从舟上取下。
  2. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(1)中，炉管内部温度为450～600℃，N 2流量范围1～30slm。
  3. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(2)中，稳定温度范围560～600℃。
  4. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(2)中，O 2流量范围10～20slm，时间8～15分钟。
  5. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(3)中，抽真空，使炉管氛围为小于100mtorr状态。
  6. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(4)中，N 2流量范围100～10000sccm，回压压力范围250～1000mtorr，保持时间0.5～10min。
  7. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(4)中，N 2流量范围200～1000sccm，回压压力范围250～600mtorr，保持时间0.5～5min。
  8. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(5)中，SiH 4流量范围200～500sccm，压力300～500mtorr，时间20～60分钟。
  9. 根据权利要求1所述的一种集成隧穿氧化层的非晶硅制备方法，其特征是，步骤(7)中，降温温度范围400～550℃。
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