| dc.description.abstract | The use of self-made plasma-assisted chemical vapor deposition (PECVD) to introduce indium methane (SiH4), hydrogen (H2), and argon (Ar) to produce an ultra-thin hydrogenated amorphous germanium passivation layer (< 10 nm) on a germanium substrate, The use of optical emission spectroscopic end-point detection to provide immediate plasma changes through plasma diagnostics drastically reduces process testing experiments and reduces process development costs.
According to the study of hydrogen dilution ratio (R=H2/SiH4), a-Si:H was deposited. During the study, the plasma spectroscopic measurement was performed by light emission spectroscopy, and the SiH* intensity represented the principal component analysis in machine learning ( PCA) combined with the trend of industry 4.0, making the process more stable. The instantaneous plasma time-series spectrum reveals the relationship between the SiH* intensity of the plasma dissociation instant (transient) and the RF input voltage and reflected voltage. At the same time, the Z-Scan sees the cavity impedance and phase, and is matched with the light emission spectrometer. The quadrupole mass spectrometer performs an immediate plasma diagnostic analysis to find out the relationship between the plasma configuration and the impedance matching. From this conclusion, the main key to improve the film quality is studied, and the process time is shortened more efficiently. Among them, film properties such as FTIR (hydrogen content) and lifetime (carrier life cycle) were measured and verified in case studies. The results of the study show that when the PCA results are greater than 0.2, the carrier lifetime can exceed 600 us or more. By Smith′s matching process, when the transient time is shorter about 1-2 seconds, a better carrier lifetime can be obtained up to 750us. The above research and analysis results can obtain appropriate process parameters and impedance matching conditions in this PECVD system. | en_US |