DuPont Central Research & Development, Experimental Station, Wilmington, Delaware 19880-500, USA.
ACS Appl Mater Interfaces. 2011 Feb;3(2):606-11. doi: 10.1021/am1011996. Epub 2011 Feb 3.
Silver metallization pastes for crystalline silicon PV cells containing nanosized metallic zinc were found to be superior to commercial pastes containing micrometer-sized metallic zinc and micrometer sized zinc oxide in terms of efficiency and firing window. Efficiency performance decreases as the size of the particles increases: nano-Zn > 3.6 μm Zn > 4.4 μm Zn. Advanced electron microscopy techniques were used to investigate the interfacial microstructure between the front-side contact and the Si emitter of nanosized zinc additive based cells fired at temperatures from below to above optimal. These microstructural observations confirmed the possibility of a tunneling mechanism of current flow (a "nano-Ag colloid assisted tunneling" model) in the absence of Ag crystallites. Contact resistance maps were used to guide sampling, leading to a better understanding of the relationship between microstructure and contact resistance. Low contact resistance and higher cell efficiency, especially at under- and overfiring temperature conditions, are due to more uniform silicon nitride etching obtained through the use of nanosized metallic zinc additives.
含纳米尺寸金属锌的晶体硅光伏电池的银金属化浆料在效率和烧结窗口方面优于含有微米尺寸金属锌和微米尺寸氧化锌的商业浆料。随着颗粒尺寸的增加，效率性能下降：纳米 Zn > 3.6μm Zn > 4.4μm Zn。先进的电子显微镜技术被用于研究在低于和高于最佳温度下烧结的基于纳米尺寸锌添加剂的电池的前侧接触和 Si 发射极之间的界面微观结构。这些微观结构观察证实了在没有 Ag 纳米晶的情况下电流流动的隧道机制（“纳米 Ag 胶体辅助隧道”模型）的可能性。接触电阻图被用于指导采样，从而更好地理解微观结构和接触电阻之间的关系。低接触电阻和更高的电池效率，特别是在欠烧和过烧温度条件下，是由于通过使用纳米尺寸的金属锌添加剂获得了更均匀的氮化硅蚀刻。
