一种分析三维楔脊形光波导与光纤耦合的方法

和直波导的不同在于,三维楔脊形波导中的光场都是不稳定的.分别对波导-光纤耦合、光纤-波导耦合两种情况,将三维楔脊形波导等效为多段短的直波导,利用束传播法同时对三维楔脊形波导内不稳定的入射、反射场,及它们在传播方向上的偏导进行处理,再用自由空间辐射模法计算透射率和反射率.以SOI楔脊形波导和光纤的耦合为例,验证了该方法的可行性.

部分耗尽型注氟SIMOX器件的电离辐射效应

采用在SIMOX圆片埋氧层中注入氟(F)离子的方法改善SIMOX的抗总剂量辐射能力,通过比较未注F样品和注F样品辐照前后SIMOX器件Ids-Vgs特性和阈值电压,发现F具有抑制辐射感生pMOSFET和nMOSFET阈值电压漂移的能力,并且可以减小nMOSFET中由辐照所产生的漏电流.说明在SOI材料中前后Si/SiO2界面处的F可以减少空穴陷阱密度,有助于提高SIMOX的抗总剂量辐射能力.

硅基微电子新材料SGOI薄膜研究进展

绝缘体上的锗硅技术(SiGeonInsulator,SGOI)和以它为衬底开发的应变硅技术(StrainedSilicononInsulator,sSOI)融合了SiGe技术和SOI技术二者的优点,是近年来人们广泛重视的研究热点和硅基集成电路产业进一步发展的重要研究方向,是国际半导体技术发展路线图(ITRS)中CMOS技术今后几年发展的方向.文章综述了SGOI薄膜的多种制备方法和最新研究进展.

厚表层Si柔性绝缘衬底上SiC薄膜的外延生长

利用LPCVD方法,在厚表层Si(SOL≈0.5μm)柔性绝缘衬底(SOI)(001)上外延生长出了可与硅衬底上外延晶体质量相比拟的SiC/SOI,表明SOI是一种很有潜力的柔性衬底. Raman 光谱结果表明SiC/SOI外延层比SiC/Si外延层有更大的残存应力,对此从理论上进行了解释.利用X射线衍射(XRD)、原子力显微镜(AFM)、扫描电镜(SEM)和喇曼散射光谱(RAM)技术研究了外延材料的晶体结构、界面性质和应变情况.

Fabrication of SiGe/Si Multi-Quantum Wells Resonant-Cavity-Enhanced Detector

A SiGe/Si multi-quantum wells resonant-cavity-enhanced(RCE) detector with high reflectivity bottom mirror is fabricated by a new method.The bottom mirror is deposited in the hole,which is etched from the backside of the sample by ethylenediamine-pyrocatechol-water(EPW) solution with the buried SiO2 layer in SOI substrate as the etching-stop layer.Reflectivity spectrum indicates that the mirror deposited in the hole has a reflectivity as high as 99% in the range of 1.2～1.5μm.The peak responsivity of the RCE detector at 1.344μm is 1.2mA/W and the full width at half maximum is 12nm.Compared with the conventional p-i-n photodetector,the responsivity of RCE detector is enhanced 8 times.

具有复合埋层的新型SIMON材料的制备

采用氮氧共注入方法制备了新型的SIMON(separation by implanted oxygen and nitrogen)SOI材料.采用不同的制备方法分别制作出样品并进行了结构测试和分析,发现SIMON材料的结构和质量对注入条件和退火工艺非常敏感.并对各种氮氧复合注入技术做了分析和比较,发现氮氧分次注入可以得到更好的结构和性能.

注氮剂量对SIMON材料性能影响的研究

采用氧氮共注的方法制备了氮氧共注隔离 SOI (SIMON) 圆片,对制备的样品进行了二次离 子质谱和透射电镜分析,并对埋层结构与抗辐射性能的机理进行了分析.结果表明,注氮剂量较低 时埋层质量较好.机理分析结果表明,圆片的抗辐照性能与埋层质量之间存在很密切的关系,埋层 的绝缘性能是影响器件抗辐射效应的关键因素.

Integrated MMI Optical Couplers and Optical Switches in Silicon-on-Insulator Technology

Integrated multimode interference (MMI) coupler based on silicon-on-insulator(SOI) has been becoming a kind of more and more attractive device in optical systems. SiO2thin cladding layers (＜1.0 μm) can be usedin SOI waveguide due to the large index step be-tween Si and SiO2, making them compatible with VLSI technology. The design and fabrica-tion of MMI optical couplers and optical switches in SOI technology are presented in thepa-per. We demonstrated the switching time of 2 × 2 MMI-MZI thermo-optical switch is less than 20 μs:

Multimode Interference Couplers with Different Background Refractive Index *

A novel structure of MMI coupler with different background refractive index has been designed. With stronger optical confinement in multimode waveguides, more guided modes are excited to improve imaging quality. Two-dimensional finite difference beam propagation method (2-D FDBPM) was used to simulate this new structure and had proven that its imaging quality, in terms of power uniformity and excess loss, is much better than conventional structure. This structure can be applied in SOI rib waveguides by deep etching method.

在解复用模块设计中有效折射率变化的研究

研究了基于SOI（silicon-on-insulator）材料的阵列波导光栅（AWG）分波器件，给出了此器件材料色散的数值拟合公式，进而利用BPM方法研究了材料色散脊型波导结构变化和器件制做中刻蚀深度误差对波导有效折射率和波分复用模块性能的影响。结果表明，刻蚀深度误差对模块性能优劣起关键作用。

MMI阵列波导光栅复用/解复用器的研制

详细分析了基于自镜像效应的MMI DMUX器件的基本工作原理，在此基础上，在SOI材料上完成了对8信道MMI DMUX的具体设计。该器件的输入、输出单模波导采用Soref的大截面脊形光波导理论进行优化设计，最后获得了当输入、输出单模波导宽度为5μm,SIE多模波导宽度和长度分别为72μm和6313.4μm时，该器件对8信道波长的隔离度均在35dB以上，且理论传输损耗<0.18dB。

Integrated tapered MMI couplers in the silicon-on-insulator technology

The authors have designed and fabricated 2x2 parabolically tapered MMI coupler with large cross-section and large space between difference ports using Silicon-on-Insulator ( SOI) technology. The devices demonstrate a minimum uniformity of 0.8dB and 30% shorter than the straight MMI coupler.

Integrated MMI optical couplers and optical switches in Silicon-on-insulator technology

Integrated multimode interference coupler based on silicon-on-insulator has been become a kind of more and more attractive device in optical systems. Thin cladding layers (<1.0mum) can be used in SOI waveguide due to the large index step between Si and SiO2, making them compatible with the VLSI technology. Here we demonstrate the design and fabrication of multimode interference (MMI) optical couplers and optical switches in SOI technology.

Integrated multimode interference couplers in silicon-on insulator

Silicon-on insulator (SOI) is an attractive platform for the fabrication of optoelectronic integrated circuit. Thin cladding layers (< 1.0m) can be used in SOI waveguide due to the large index step between Si and SiO2, making them compatible with the VLSI technology. Here we demonstrate the fabrication of 1 x 4 and 2 x 2 multimode interference (MMI) coupler based on SOI technology. Performances of the devices are analyzed. The minimum excess loss of the devices is about 1.8dB. The devices show uniform power distribution.

Long-wavelength SiGe/Si MQW resonant-cavity-enhanced photodiodes (RCE-PD)

Si1-xGex/Si optoelectronic devices are promising for the monolithic integration with silicon-based microelectronics. SiGe/Si MQW RCE-PD (Resonant-Cavity-Enhanced photodiodes) with different structures were investigated in this work. Design and fabrication of top- and bottom-incident RCE-PD, such as growth of SiGe MQW (Multiple Quantum Wells) on Si and SOI (Si on insulator) wafers, bonding between SiGe epitaxial wafer and SOR (Surface Optical Reflector) consisting Of SiO2/Si DBR (Distributed Bragg Reflector) films on Si, and performances of RCE-PD, were presented. The responsivity of 44mA/W at 1.314 mum and the FWHM of 6nm were obtained at bias of 10V. The highest external quantum efficiency measured in the investigation is 4.2%.