CN106711244B - Ibc电池接触开孔工艺 - Google Patents

Ibc电池接触开孔工艺 Download PDF

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CN106711244B
CN106711244B CN201710046580.1A CN201710046580A CN106711244B CN 106711244 B CN106711244 B CN 106711244B CN 201710046580 A CN201710046580 A CN 201710046580A CN 106711244 B CN106711244 B CN 106711244B
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李华
鲁伟明
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Taizhou Longi Solar Technology Co Ltd
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Abstract

本发明提供一种IBC电池接触开孔工艺，在太阳能电池的发射极和背场上形成介质膜；在介质膜上丝网印刷或者喷墨打印烧穿浆料形成导电触点图案；通过退火，烧穿浆料与介质膜相互作用，导电触点图案处形成开孔区域，使用表面活性剂进行清洗处理，在导电触点处掺杂的硅被暴露出来；其他地方仍保留介质膜；该种IBC电池接触开孔工艺，能够形成清晰度高的、成本低的金属化开孔。本发明通过利用烧穿浆料在高温下与沉积的介质绝缘膜发生反应形成太阳能电池局部电接触的图案，由此满足降低工艺复杂性和相应的生产成本的要求。

Description

IBC电池接触开孔工艺
技术领域
本发明涉及一种IBC电池接触开孔工艺。
背景技术
IBC(Interdigitated back contact指交叉背接触)电池，是指电池正面无电极，正负两极金属栅线呈指状交叉排列于电池背面。IBC电池最大的特点是PN结和金属接触都处于电池的背面，正面没有金属电极遮挡的影响，因此具有更高的短路电流Jsc，同时背面可以容许较宽的金属栅线来降低串联电阻Rs从而提高填充因子FF；加上电池前表面场(Front Surface Field,FSF)以及良好钝化作用带来的开路电压增益，使得这种正面无遮挡的电池不仅转换效率高，而且看上去更美观，同时，全背电极的组件更易于装配。IBC电池是目前实现高效晶体硅电池的技术方向之一。
目前IBC电池实现金属化工程中需要在介质膜上生成接触孔，通常采用光刻、激光开孔和腐蚀浆料的方法进行，光刻法比较昂贵，激光开孔容易对介质膜下的结区造成损伤，腐蚀浆料开孔，受到印刷能力的限制，开孔的区域往往比较大，而且边缘不清晰。
上述问题是在IBC电池的生产过程中应当予以考虑并解决的问题。
发明内容
本发明的目的是提供一种IBC电池接触开孔工艺解决现有技术中存在的光刻法比较昂贵，激光开孔容易对介质膜下的结区造成损伤，腐蚀浆料开孔开孔的区域往往比较大，而且边缘不清晰等问题。
本发明的技术解决方案是：
一种IBC电池接触开孔工艺，在太阳能电池的发射极和背场上形成介质膜；在介质膜上丝网印刷或者喷墨打印烧穿浆料形成导电触点图案；通过退火，烧穿浆料与介质膜相互作用，导电触点图案形成开孔区域；使用清洗剂进行清洗处理，在导电触点处掺杂的硅暴露出来，其他地方仍保留介质膜。
进一步地，介质膜包括钝化介质层和抗反射膜，包括SiNx、SiO2、SiOxNy、TiO2、Al2O3中的一种或多种。
进一步地，烧穿浆料包括溶剂、触变剂、表面活性剂和玻璃粉末。
进一步地，溶剂包括松节油、松油醇、二乙二醇丁醚醋酸脂、二乙二醇丁醚中的一种或多种；触变剂包括树胶、淀粉、气相二氧化硅中的一种或者几种；表面活性剂包括卵磷脂、环己酮中的一种或几种；玻璃粉末成分包括PbO、B2O3、Bi2O3、SiO2、Al2O3、ZnO、CaO、TiO2、V2O5、Li2O、MgO中的一种或多种。
进一步地，表面活性剂包括卵磷脂、乙醇、环己酮。清洗剂为含有F离子的溶剂，包括HF、NH4F、NaF、KF中的一种或者几种。
进一步地，导电触点图案为连续的或分离的规则图形、不规则图形。
进一步地，导电触点图案为直线时，采用线条宽度为30-100微米的连续直线形或分段直线形。
进一步地，导电触点图案为分离的图形时，每个导电触点图案的面积为2000平方微米到30000平方微米。
进一步地，退火温度为400-900度，时间为30s-20min。
进一步地，采用浓度为0.5％-5％的清洗剂进行清洗，去除剩余的烧穿浆料，然后在发射极和背场区域分别印刷接触浆料，烧结后，接触浆料通过开孔处分别与发射极、背场区域实现局部接触，分别得到正极电极和负极电极。
本发明的有益效果是：该种IBC电池接触开孔工艺，能够形成清晰度高的、成本低的金属化开孔。本发明通过利用烧穿浆料在高温下与沉积的介质绝缘膜发生反应形成太阳能电池局部电接触的图案，由此满足降低复杂性和相应的生产成本的要求。
附图说明
图1是在基体上形成背面发射极和背场区域的结构示意图；
图2是实施例中在发射极背场上形成介质膜的结构示意图；
图3是实施例中介质膜上印刷烧穿浆料退火的示意图；
图4是实施例中退火清洗后形成掺杂层上的开孔区域的示意图；
图5是实施例中金属化后电极通过开孔区域与掺杂层形成欧姆接触的示意图；
图6是实施例一中导电触点图案的示意图；
图7是实施例二中导电触点图案的示意图；
图中：1-发射极，2-背场，3-介质膜，4-烧穿浆料5-开孔区域6-正极电极7-负极电极，8-前表面场，9-钝化减反膜，10-基体。
具体实施方式
下面结合附图详细说明本发明的优选实施例。
一种IBC电池接触开孔工艺，在太阳能电池的发射极1和背场2上形成介质膜3，如图2；在介质膜3上丝网印刷或者喷墨打印烧穿浆料4形成导电触点图案，如图3；通过退火，烧穿浆料4与介质膜3相互作用，导电触点图案形成开孔区域5，如图4；使用清洗剂进行清洗处理，在导电触点处掺杂的硅暴露，其他地方仍保留介质膜3。
烧穿浆料4包括溶剂、触变剂、表面活性剂和玻璃粉末。溶剂包括松节油、松油醇、二乙二醇丁醚醋酸脂、二乙二醇丁醚中的一种或多种；触变剂包括树胶、淀粉、气相二氧化硅中的一种或者几种；表面活性剂包括卵磷脂、环己酮中的一种或几种；玻璃粉末成分包括PbO、B2O3、Bi2O3、SiO2、Al2O3、ZnO、CaO、TiO2、V2O5、Li2O、MgO中的一种或多种。
介质膜3包括钝化介质层和抗反射膜，包括SiNx、SiO2、SiOxNy、TiO2、Al2O3中的一种或多种。
实施例一
IBC电池经过清洗，扩散，如图1，在基体上形成背面发射极和背场区域，在太阳能电池的发射极1和背场2上形成介质膜3，如图2；背表面镀膜后在发射极1和背场2区域对应的区域印刷含有烧穿浆料4，烧穿浆料4中含有PbO 50％、B2O3 10％、SiO2 25％、Al2O3 5％、ZnO 5％、Li2O 5％。如图6，印刷后图形宽度为50微米，长度为100微米，垂直方向上相邻图形的间距为1.5mm，进行250℃烘干，840℃下烧结2min，烧穿浆料4与介质膜3发生反应，形成开孔区域5，且烧穿浆料4并不与介质膜3下的掺杂层发生反应。
将烧结后的电池片采用浓度为2％的清洗剂HF溶液，清洗15秒，去除剩余的烧穿浆料4，然后在发射极1和背场2区域分别印刷接触浆料，烧结后，接触浆料通过开孔处与发射极1和背场2区域实现局部接触，如图5所示，分别得到正极电极6和负极电极7。电池片的正面依次设有前表面场8和钝化减反膜9。
实施例二
IBC电池经过清洗，扩散，如图1，在基体上形成背面发射极和背场区域，在太阳能电池的发射极1和背场2上形成介质膜3，如图2；背表面镀膜后在发射极1和背场2区域对应的区域印刷烧穿浆料4，即含有玻璃料的浆料，烧穿浆料4含有PbO 60％、B2O3 5％、SiO220％、Al2O3 3％、ZnO 7％、NaO 5％。如图7，印刷后图形为圆形，直径为50微米，垂直方向上相邻图形的间距为1.5mm，进行250℃烘干，840℃下烧结1.5min，烧穿浆料4与介质膜3发生反应，形成开孔区域5，烧穿浆料4并不与介质膜3下的掺杂层发生反应。
将烧结后的电池片采用浓度为5％的NH4F溶液，清洗30秒，去除剩余的玻璃料，然后在发射极1和背场2区域分别印刷接触浆料，烧结后，接触浆料通过开孔处与发射极1和背场2区域实现局部接触，分别得到正极电极6和负极电极7。
实施例一、二的IBC电池接触开孔工艺，能够形成清晰度高的、成本低的金属化开孔。实施例通过利用烧穿浆料4在高温下与沉积的介质绝缘膜发生反应形成太阳能电池局部电接触的图案，由此满足降低复杂性和相应的生产成本的要求。

Claims (8)

1.一种IBC电池接触开孔工艺，其特征在于：在太阳能电池的发射极和背场上形成介质膜；在介质膜上丝网印刷或者喷墨打印烧穿浆料形成导电触点图案；通过退火，烧穿浆料与介质膜相互作用，导电触点图案形成开孔区域；使用清洗剂进行清洗处理，在导电触点处掺杂的硅暴露出来，其他地方仍保留介质膜；其中，
烧穿浆料包括溶剂、触变剂、表面活性剂和玻璃粉末；溶剂包括松节油、松油醇、二乙二醇丁醚醋酸脂、二乙二醇丁醚中的一种或多种；触变剂包括树胶、淀粉、气相二氧化硅中的一种或者几种；表面活性剂包括卵磷脂、环己酮中的一种或几种；玻璃粉末成分包括PbO、B2O3、Bi2O3、SiO2、Al2O3、ZnO、CaO、TiO2、V2O5、Li2O、MgO中的一种或多种。
2.如权利要求1所述的IBC电池接触开孔工艺，其特征在于：介质膜包括钝化介质层和抗反射膜，包括SiNx、SiO2、SiOxNy、TiO2、Al2O3中的一种或多种。
3.如权利要求1或2所述的IBC电池接触开孔工艺，其特征在于：清洗剂为含有F离子的溶剂，包括HF、NH4F 、NaF、KF中的一种或者几种。
4.如权利要求1或2所述的IBC电池接触开孔工艺，其特征在于：导电触点图案为连续的或分离的规则图形、不规则图形。
5.如权利要求4所述的IBC电池接触开孔工艺，其特征在于：导电触点图案为直线时，采用线条宽度为30-100微米的连续直线形或分段直线形。
6.如权利要求4所述的IBC电池接触开孔工艺，其特征在于：当为分离的图形时，每个导电触点图案的面积为2000平方微米到30000平方微米。
7.如权利要求1或2所述的IBC电池接触开孔工艺，其特征在于：退火温度为400-900度，时间为30s-20min。
8.如权利要求1或2所述的IBC电池接触开孔工艺，其特征在于：采用浓度为0.5％-5％的清洗剂进行清洗，去除剩余的烧穿浆料，然后在发射极和背场区域分别印刷接触浆料，烧结后，接触浆料通过开孔处分别与发射极、背场区域实现局部接触，分别得到正极电极和负极电极。
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