dc.description.abstract | Perovskite solar cells were well study since 2009 since the high power conversion efficiency (PCE) and capable of making flexible device. However, unstable alkylammonium salts and iodine ions in the absorption layer lead to the perovskite solar cells low reliability in high humidity ambient. Except the modification of absorption layer or the design structure of perovskite solar cells, the package process can also effectively improve the stability. Despite the common glass-glass sandwich structure with organic sealing can pass the damp heat test, the over-size package will reduce the power per unit volume of thin film solar cell. Therefore, the package structure with nitride/oxide surface passivation film blocking the oxygen and humidity was studied. The Al oxide deposited by ALD was the most effective process, however, the less process-area and time-consuming shortcoming making it hard to commercialize. In order to solve the packing issue mention above, we develop the flip-chip package process of the perovskite solar cells in the Chapter 4. The flip –chip package process was developed with PECVD Si nitride film with chemical materials, low temperature (< 90 ℃) Sn-Bi-In solders and pattern glass substrate. From the reliability test, we surprising finds packaged solar cells remain 90.2 % in the DI-water ambient, however, it only remains 79 % in the N2 ambient (570 hours). We consider not the amount but the ratio of oxygen/humidity in the ambient related with risk index of the packaged perovskite solar cell. In the chapter 5, we analyzed the failure mechanism of different residual stress Si nitride film in the N2, O2 and H2O ambient, which depends on [Si-H]/[Si-N]. From the Fourier-transform infrared spectroscopy (FTIR), we finds the Si-H bonds were passivated by the Si-N bonds. From the Scanning Electron Microscope (SEM), the residual stress enhanced the gas diffusion into the nitride-metal interface. In the oxygen/humidity hybrid ambient, the oxygen was consider as the ambient buffer to decrease the oxidation by conducting the surface competitive adsorption. However, the oxygen acted as ambient buffer was vanished since increasing of oxygen, the delamination happened as well. We finds the Si nitride oxidation depends not only the intrinsic property ([Si-H]/[Si-N]) but also oxygen/humidity of ambient. According to the analysis above, this study illustrated the delamination mechanism of Si nitride film under O2 and H2O ambient. Finally, after understanding the oxidation and delamination, we recognized the delamination of Si nitride film in the oxygen/humidity hybrid ambient. | en_US |