Font Size: a A A

Dielectric Micro-cavity Arrays Based Light Manipulation And Its Application In Photodetectors

Posted on:2020-12-13Degree:MasterType:Thesis
Country:ChinaCandidate:A N YingFull Text:PDF
GTID:2428330572480742Subject:Condensed matter physics
Abstract/Summary:PDF Full Text Request
Recently,the advanced light manipulation technology has been considered as the most important approach to realize the efficient photodetecting enhancement in broadband or specific wavelength region for photodetectors(PDs).The advanced three-dimensional micro-nano structure based light manipulation is considered to be the most effective way to improve the photoresponse of photodetectors.As a most attractive micro-nano structure in light manipulation field,whispering gallery mode(WGM)resonant optical cavities can manipulate light in different wavelength region through the multiple resonance modes by enhancing the light-matter interactions in the cavity or coupling the light into the under-layer substrates through the waveguide mode.Theoretically,different from the conventionally used optical film technology,this kind of multiple resonances should be possible for application in PDs for the specific wavelength manipulation or broadband light trapping enhancement.However,the further theoretical and experimental research on the optical microcavity need to be studied in terms of light manipulation mechanism,method and corresponding optical response enhancement on photodetectors.In this thesis,with the concern of mentioned questions above,we conducted research as follows:Firstly,the fabrication process of silicon-based photodetector,construction of three-dimensional dielectric microcavity and integration technology were developed.On the one hand,silicon-based photodetectors with stable fabrication process can be prepared by means of ion implantation,rapid annealing,standard cleaning,photolithography,Plasma Enhanced Chemical Vapor Deposition(PECVD)growth,metal/semiconductor thin film deposition,dicing,electrode bonding and packaging.On the other hand,through the Polystyrene(PS)nanosphere self-assembled technology,combined with the nanosphere size adjustment and high temperature annealing process,the stable three-dimensional dielectric microcavity arrays were effectively prepared,which established the foundation for the subsequent application of silicon-based photodetector.Secondly,the structure optimization and performance evaluation of traditional silicon-based photodetectors were conducted.In this part,we prepared single-injection NIP optoelectronic device with an epitaxially grown ?-type layer and double-inj ection PIN and NIP devices with high-resistance silicon as the ?-layer.In addition,we improved the light absorption and optical responsivity of the device in the peak response band by optimizing the anti-reflective layer.Finally,an encapsulated double-injection PIN device with optimizing anti-reflective layer was successfully achieved as an excellent narrow-band(F WHM<200nm)visible blind near-infrared PD,demonstrating great prospects in short-wave infrared communication,night vision imaging and security applications.Lastly,light trapping mechanism research of microcavity structure and its application in photodetection performance improvement were conducted.We proposed a new strategy for light trapping enhancement within a broadband and specific wavelength region for PDs by utilizing the multiple Whispering Gallery Mode(WGM)resonances generated in ZnO microcavity arrays(MCAs).Both theoretical and experimental results indicated that the leaky mode radiation of the WGM resonances,which most effectively work in the off-resonance region,is the main enhancement mechanism for light trapping.Consequently,by introducing the ZnO MCAs with further manipulating the WGM resonance peaks and resonance quality on the Si-based PIN PDs,besides a broadband photoresponsivity enhancement within nearly the whole UV-VIS-NIR region,a responsivity enhancement up to 25%within the commonly used optical communication and sensing region(800 to 980 nm)was accomplished compared to the control detectors.This work well demonstrated that the leaky modes of WGM resonant dielectric cavity arrays can effectively improve the light trapping and thus responsivity in broadband or selective spectra for photodetection and will enable future exploration of their applications in other photoelectric conversion devices.
Keywords/Search Tags:Dielectric micro cavity, Light manipulation, WGM resonance, Leaky mode, Silicon-based photodetector, Responsivity enhancement
PDF Full Text Request
Related items