Research on quantum well intermixing of 680 nm AlGaInP/GaInP semiconductor lasers induced by composited Si-Si_(3)N_(4) dielectric layer

The optical catastrophic damage that usually occurs at the cavity surface of semiconductor lasers has become the main bottleneck affecting the improvement of laser output power and long-term reliability.To improve the output power of 680 nm AlGaInP/GaInP quantum well red semiconductor lasers,Si-Si_(3)N_(4)composited dielectric layers are used to induce its quantum wells to be intermixed at the cavity surface to make a non-absorption window.Si with a thickness of 100 nm and Si_(3)N_(4)with a thickness of 100 nm were grown on the surface of the epitaxial wafer by magnetron sputtering and PECVD as diffusion source and driving source,respectively.Compared with traditional Si impurity induced quantum well intermixing,this paper realizes the blue shift of 54.8 nm in the nonabsorbent window region at a lower annealing temperature of 600 ℃ and annealing time of 10 min.Under this annealing condition,the wavelength of the gain luminescence region basically does not shift to short wavelength,and the surface morphology of the whole epitaxial wafer remains fine after annealing.The application of this process condition can reduce the difficulty of production and save cost,which provides an effective method for upcoming fabrication.

Plasma-enhanced Chemical Vapordeposition SiO_2 Film after Ion Implantation Induces Quantum Well Intermixing

A method of QWI （ quantum well intermixing） realizing through plasma-enhanced chemical vapordepositiom （PECVD） SiO2 film following ion implantation was investigated. PECVD 200 mn SiO2 film after 160 keV phosphorus（P） ion implantation was performed to induce InP-based multiple-quantum-well （MQW） laser structural intermixing, annealing process was carried out at 780 ℃ for 30 seconds under N2 flue, the blue shift ofphotoluminescenee （PL） peak related to implanted dose ： 1 × 10^11, 1 × 10^12, 1×10^13 ,3 × 10^13 , 7× 10^13 ion/ cm^2 is 22 nm, 65 nm, 104 nm, 109 nm, 101 nm, respectively. Under the same conditions, by comparing the blue shift of PL peak with P ion implantation only, slight differentiation between the two methods was observed, and results reveal that the defects in the implanting layers generated by ion implantation are much more than those in SiO2 film. So, the blue shift results mainly from ion implantation. However, SiO2 film also may promote the quantum well intermixing.

Monolithic integration of electroabsorption modulators and tunnel injection distributed feedback lasers using quantum well intermixing

Electroabsorption modulators combining Franz-Keldysh effect and quantum confined Stark effect have been mono-lithically integrated with tunnel-injection quantum-well distributed feedback lasers using a quantum well intermixing method. Superior characteristics such as extinction ratio and temperature insensitivity have been demonstrated at wide temperature ranges.

Wavelength Tuning in the Two-Section Distributed Bragg Reflector Laser Fabricatedby Quantum-Well Intermixing

The two-section tunable ridge waveguide distributed Bragg reflector (DBR) lasers fabricated by strained In xGa1-xAsyP1-y The threshold current of the laser is 51mA. The tunable range of the laser is 3.2nm and the side mode suppression ratio (SMSR) is more than 38dB.

Simple Approach on Intermixing Solar and Wind Energy and Minimizing Their Intermittent Effect

Renewable energy resources especially wind and solar energy are emerging as the modern power sources to electrify remote areas. The main reason behind their emergence is due to their environment-friendly behavior,unlimited availability and short period for replenishment over nonrenewable energy resources. Renewable energy resources are much better than nonrenewable energy resources, but the intermittency in renewable energy resources degrades the system performance. In order to overcome the intermittency, multiple hybrid system techniques were proposed in literature that can achieve suitable results but have disadvantages of complicated control structures and high implementation cost. Considering aforementioned shortcomings, a simple balancing approach is proposed to intermix solar and wind energy together so as to utilize the available energy from both sources at a given time.It is very common that solar farms are the dominating source of energy in daytime and summer, while wind farms are the dominating source of energy at night and in winter. The proposed approach delivers maximum possible power to the load by combining dominating and non-dominating resources all the time, hence mitigating the intermittency of individual resources. Compared with other approaches, the proposed approach offers key benefits with redundancy, simple design and low cost, which can be analyzed from simulation results.

Spatial control based quantum well intermixing in InP/InGaAsP structures using ICP

This paper presents a new method based on spatial controlling in quantum well intermixing in InP/InGaAsP structures using ICP technology.The degree of bandgap energy shift in the same wafer can be controlled flexibly using masks with different duty ratios.With an optimal condition including ICP-RIE etching depth, SiO_2 deposition,and RTA process,five different degrees of blue-shift with maximum of 75 nm were obtained in the same sample.The result shows that our method is an effective way to fabricate monolithic integration devices, especially in multi-bandgap structures.

Van der Waals interfacial bonding and intermixing in GeTe-Sb2Te3-based superlattices

Interfacial phase change memory （iPCM） based on GeTe and Sb2Te3 superlattices （SLs） is an emerging contender for non-volatile data storage applications. A detailed knowledge of the atomic structure of these materials is crucial for further development of SLs and for a better understanding of the resistivity switching characteristics of iPCM devices. In this work, crystalline GeTe-Sb2TeB- based SLs, produced by pulsed laser deposition onto a Si（111） substrate at temperatures lower than in previous studies, are analyzed by advanced scanning transmission electron microscopy. The results reveal the formation of Ge-rich Ge（x＋y）Sb（2-y）Tez building blocks with specific numbers of ordered Ge cation layers （between I and 5） and disordered cation layers （4） for z = 6-10, as well as intermixed cation layers for z = 5, within the SLs. The G Ge（x＋y）Sb（2-y）Tez units are separated from the Sb2Te3 building blocks by van der Waals gaps. In particular, the interlayer bonding is promoted by the formation of outermost cation layers consisting of intermixed GeSb within the building blocks adjacent to the van der Waals gaps. The Ge（x＋y）Sb（2-y）Tez units with z 〉 5 retain metastable crystal structures with two-dimensional bonding within the SLs. The present study shed new light on the possible configurations of the building units that can be formed during the synthesis of GeTe-Sb2Te3-based iPCM materials. In addition, a possible switching mechanism active in iPCM materials is discussed.

Study of quantum well mixing induced by impurity-free vacancy in the primary epitaxial wafers of a 915 nm semiconductor laser

Output power and reliability are the most important characteristic parameters of semiconductor lasers.However,catas-trophic optical damage(COD),which usually occurs on the cavity surface,will seriously damage the further improvement of the output power and affect the reliability.To improve the anti-optical disaster ability of the cavity surface,a non-absorption window(NAW)is adopted for the 915 nm InGaAsP/GaAsP single-quantum well semiconductor laser using quantum well mix-ing(QWI)induced by impurity-free vacancy.Both the principle and the process of point defect diffusion are described in detail in this paper.We also studied the effects of annealing temperature,annealing time,and the thickness of SiO_(2) film on the quan-tum well mixing in a semiconductor laser with a primary epitaxial structure,which is distinct from the previous structures.We found that when compared with the complete epitaxial structure,the blue shift of the semiconductor laser with the primary epi-taxial structure is larger under the same conditions.To obtain the appropriate blue shift window,the primary epitaxial struc-ture can use a lower annealing temperature and shorter annealing time.In addition,the process is less expensive.We also pro-vide references for upcoming device fabrication.

Dual-wavelength distributed Bragg reflector semiconductor laser based on a composite resonant cavity

We report a monolithic integrated dual-wavelength laser diode based on a distributed Bragg reflector （DBR） composite resonant cavity. The device consists of three sections, a DBR grating section, a passive phase section, and an active gain section. The gain section facet is cleaved to work as a laser cavity mirror. The other laser mirror is the DBR grating, which also functions as a wavelength filter and can control the number of wavelengths involved in the laser action. The reflection bandwidth of the DBR grating is fabricated to have an appropriate value to make the device work at the dual-wavelength lasing state. We adopt the quantum well intermixing （QWI） technique to provide low-absorption loss grating and passive phase section in the fabrication process. By tuning the injection currents on the DBR and the gain sections, the device can generate 0.596 nm-spaced dual-wavelength lasing at room temperature.

间歇式混炼的相切型和啮合型密炼机(上)

对“相切型和啮合型”这两种间歇式混炼密炼机的主要部件结构及设计、工艺配方、投料方式及混炼过程的填充系数、上顶栓下落位置、温度控制、密炼机旋转速度等都做了较详细的探讨。介绍了“NST”新型转子在实验和生产中的运行情况,并与传统剪切转子做了比较,证实其生产能力和产出的混炼胶质量都有很大提高。

Fabrication of GaAs/SiO_(2)/Si and GaAs/Si heterointerfaces by surface-activated chemical bonding at room temperature

The room-temperature(RT)bonding mechanisms of Ga As/Si O_(2)/Si and Ga As/Si heterointerfaces fabricated by surface-activated bonding(SAB)are investigated using a focused ion beam(FIB)system,cross-sectional scanning transmission electron microscopy(TEM),energy dispersive x-ray spectroscopy(EDX)and scanning acoustic microscopy(SAM).According to the element distribution detected by TEM and EDX,it is found that an intermixing process occurs among different atoms at the heterointerface during the RT bonding process following the surface-activation treatment.The diffusion of atoms at the interface is enhanced by the point defects introduced by the process of surface activation.We can confirm that through the point defects,a strong heterointerface can be created at RT.The measured bonding energies of Ga As/Si O_(2)/Si and Ga As/Si wafers are 0.7 J/m^(2)and 0.6 J/m^(2).The surface-activation process can not only remove surface oxides and generate dangling bonds,but also enhance the atomic diffusivity at the interface.

间歇式混炼的相切型和啮合型密炼机(下)

对“相切型和啮合型”这两种间歇式混炼密炼机的主要部件结构及设计;工艺配方、投料方式及混炼过程的填充系数、上顶栓下落位置、温度控制、密炼机旋转速度等都做了较详细的探讨。介绍了“NST”新型转子在实验和生产中的运行情况,并与传统剪切转子做了比较,证实其生产能力和产出的混炼胶质量都明显有很大提高。

三一国际并购再打闪电战

7月23日晚间，三一重工发布公告称，公司控股子公司德国普茨迈斯特公司（简称“普茨迈斯特”），日前与Hans—George Stetter先生签署《股权转让协议》，普茨迈斯特出资810万欧元收购Hans-GeorgeStetter先生持有的Intermix GmbH公司100％的股权。

面孔

三年前，新闻集团董事长鲁们特·默多克以5．8亿美元收购Intermix Media,将MySpace揽入旗下。根据对用户价值的不同衡量标准，MySpace目前市值最高达到200亿美元。而且与大多数幸十交网站不同的是，MySpace已经实现了盈利。在10月17日的股东大会上，默多克表示，新闻集团持有50亿美元的现金，足以应对当前的全球经济危机。

Frequency and wavelength tunable optical microwave source based on a distributed Bragg reflector self-pulsation laser

A frequency and wavelength tunable self-pulsation laser based on DBR laser devices is reported for the first time.This laser generates continuous tunable optical microwave in the range of 1.87-21.81 GHz with 3-dB linewidth about 10 MHz by tuning the injection currents on the front and back gain sections,and exhibits wavelength tuning range from 1536.28 to 1538.73 nm by tuning the injection currents on the grating section.

High-performance electroabsorption modulator

A 100-μm-long electroabsorption modulator monolithically integrated with passive waveguides at the input and output ports is fabricated through ion implantation induced quantum well intermixing, using only a twostep low-pressure metal-organic vapor phase epitaxial process. An InGaAsP/InGaAsP intra-step quantum well is introduced to the active region to improve the modulation properties. In the experiment high modulation speed and high extinction ratio are obtained simultaneously, the electrical-to-optical frequency response （E/O response） without any load termination reaches to 22 GHz, and extinction ration is as high as 16 dB.

Design optimized intermixed phase by tuning polymer-fullerene intercalation for free charge generation

The inte rmixed phase is important in effective charge separation due to the formation of cascaded energy landscape between intermixed phase and pure phases in polymer/fullerene solar cells.However,the quantitative relationship between the charge separation and the content of intermixed phase has not been investigated clearly so far.Here,we proposed to tune the content of the polymer/PC71BM intermixed phase by cha nging the polymer solution conformatio n.Poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene](PBTTT)and PC71 BM was selected as a model system.The organization of the PBTTT in solution promotes the formation of ordered aggregates as aging time increases,the interdigitation of side-chains restricts the intercalation of PC71 BM.Therefore,the intermixed phase formed by intercalation PC71 BM to PBTTT side chain can be controlled.When the aging time increasing from 0 to 80 min,the extent of inte rcalation gradually from almost complete intercalated phase to almost non-intercalated.As the content of intercalated phase is about 11%,the charge dissociation is most efficie nt and short circuit current(Jsc)increased from 1.60 mA/cm2 to 4.94 mA/cm2,leading to optimized device performance.