酸刻蚀处理对Si(100)和Si(111)上制备CVD金刚石膜的影响

对Si(100)和Si(111)采用相同的酸刻蚀工艺,采用热丝化学气相沉积法(HFCVD)制备金刚石膜。用扫描电子显微镜、X线衍射仪和X线应力测试仪对样品的形貌、织构及残余应力进行检测、分析。研究结果表明:沉积3 h后,Si(100)和Si(111)基体上均生长出晶形比较完整,呈柱状晶方式生长的金刚石薄膜;此外,Si(100)金刚石膜表面分布着大量的微孔,通过调整沉积工艺可控制微孔的数量和尺寸,而Si(111)金刚石膜表面无微孔出现;2种基体所得薄膜都存在(111)织构,后者Si(111)还有一定的(110)织构;2种基体经酸刻蚀之后制得薄膜均无鼓泡剥离现象,二者的残余应力相差不大。

A large bandwidth photonic delay line using passive cascaded silicon-on-insulator microring resonators

This paper investigated the design and the characterization of a photonic delay line based on passive cascaded silicon-on-insulator （SOI） microrings. We considered the compromise of group delay, bandwidth and insertion loss. A 3-stage double channel side-coupled integrated spaced sequence of resonator （SCISSOR） device was optimized by shifting the resonance of each microring and fabricated with electron beam lithography and dry etching. The group delay was measured to be 17 ps for non-return-to-zero signals at different bit rates and the bandwidth of 78 GHz was achieved. The experiment result agreed well with our simulation.

CMOS compatible highly efficient grating couplers with a stair-step blaze profile

A novel grating coupler with a stair-step blaze profile is proposed. The coupler is a CMOS process compatible device and can be used for light coupling in optical communication. The blaze profile can be optimized to obtain a high efficiency of 66.7% for the out-of-plane coupling at the centre wavelength of 1595 nm with a 1 dB bandwidth of 41 nm. Five key parameters of the stair-step blaze grating and their effects on the coupling are discussed for the application in L band telecommunication.

Modeling and analysis of silicon-on-insulator elliptical microring resonators for future high-density integrated photonic circuits

We propose a novel resonator containing an elliptical microring based on a silicon-on-insulator platform. Simu- lations using the three-dimensional finite-difference time-domain method show that the novel elliptical microring can efficiently enhance the mode coupling between straight bus waveguides and resonator waveguides or between adjacent resonators while preserving relatively high intrinsic quality factors with large free spectral range. The proposed resonator would be an alternative choice for future high-density integrated photonic circuits.

Wafer.Level Testable High-Speed Silicon Microring Modulator Integrated with Grating Couplers

A wafer-level testable silicon-on-insulator-based microring modulator is demonstrated with high modulation speed, to which the grating couplers are integrated as the fiber-to-chip interfaces. Cost-efflcient fabrications are realized with the help of optical structure and etching depth designs. Grating couplers and waveguides are patterned and etched together with the same slab thickness. Finally we obtain a 3-dB coupling bandwidth of about 6Ohm and 10 Gb/s nonreturn-to-zero modulation by wafer-level optical and electrical measurements.

硅基波导慢光器件及其应用

硅基波导慢光器件是构建全光智能互连和实时高速测控等下一代信息技术的关键器件,在光通信和光信息处理等诸多领域具有显著的技术优势和巨大的应用潜力.随着器件结构的不断创新以及微电子制造技术的不断升级换代,硅基波导慢光器件愈来愈走向实用化.文章介绍了慢光的基本原理,概述了当前国内外硅基波导慢光器件的研究进展,着重分析了基于微环谐振腔的硅基波导慢光器件,并指出了它在具体应用领域中的发展前景.