Hydrogenated amorphous silicon （a-Si：H） films with high and same order of magnitude photosensitivity （-10^5） but different stability were prepared by using microwave electron cyclotron resonance chemical vapour d...Hydrogenated amorphous silicon （a-Si：H） films with high and same order of magnitude photosensitivity （-10^5） but different stability were prepared by using microwave electron cyclotron resonance chemical vapour deposition system under the different deposition conditions. It was proposed that there was no direct correlation between the photosensitivity and the hydrogen content （CH） as well as H-Si bonding configurations, but for the stability, they were the critical factors. The experimental results indicated that higher substrate temperature, hydrogen dilution ratio and lower deposition rate played an important role in improving the microstructure of a-Si：H films. We used hydrogen elimination model to explain our experimental results.展开更多
Photodetectors operating at the wavelength in the visible spectrum are key components in high-performance optoelectronic systems.In this work,massive nonlinearities in amorphous silicon p-i-n photodiodes enabled by th...Photodetectors operating at the wavelength in the visible spectrum are key components in high-performance optoelectronic systems.In this work,massive nonlinearities in amorphous silicon p-i-n photodiodes enabled by the photogating are presented,resulting in responsivities up to 744 mA/W at blue wavelengths.The detectors exhibit significant responsivity gains at optical modulation frequencies exceeding MHz and a more than 60-fold enhanced spectral response compared to the non-gated state.The detection limits down to 10.4 nW/mm^(2) and mean signal-to-noise ratio enhancements of 8.5dB are demonstrated by illuminating the sensor with an additional 6.6μW/mm^(2) red wavelength.Electro-optical simulations verify photocarrier modulation due to defect-induced field screening to be the origin of such high responsivity gains.The experimental results validate the theory and enable the development of commercially viable and complementary metal oxide semiconductor(CMOS)compatible high responsivity photodetectors operating in the visible range for low-light level imaging and detection.展开更多
文摘Hydrogenated amorphous silicon （a-Si：H） films with high and same order of magnitude photosensitivity （-10^5） but different stability were prepared by using microwave electron cyclotron resonance chemical vapour deposition system under the different deposition conditions. It was proposed that there was no direct correlation between the photosensitivity and the hydrogen content （CH） as well as H-Si bonding configurations, but for the stability, they were the critical factors. The experimental results indicated that higher substrate temperature, hydrogen dilution ratio and lower deposition rate played an important role in improving the microstructure of a-Si：H films. We used hydrogen elimination model to explain our experimental results.
基金This work has received funding from the German Description Fund for Regional Development(Grant No.EFRE0200545)for the execution of the project and from DFG(Grant No.INST 221/131-1)for utilizing the instruments of the Micro and Nanoanalytics Facility(MNaF)for microscopy.
文摘Photodetectors operating at the wavelength in the visible spectrum are key components in high-performance optoelectronic systems.In this work,massive nonlinearities in amorphous silicon p-i-n photodiodes enabled by the photogating are presented,resulting in responsivities up to 744 mA/W at blue wavelengths.The detectors exhibit significant responsivity gains at optical modulation frequencies exceeding MHz and a more than 60-fold enhanced spectral response compared to the non-gated state.The detection limits down to 10.4 nW/mm^(2) and mean signal-to-noise ratio enhancements of 8.5dB are demonstrated by illuminating the sensor with an additional 6.6μW/mm^(2) red wavelength.Electro-optical simulations verify photocarrier modulation due to defect-induced field screening to be the origin of such high responsivity gains.The experimental results validate the theory and enable the development of commercially viable and complementary metal oxide semiconductor(CMOS)compatible high responsivity photodetectors operating in the visible range for low-light level imaging and detection.
