InAs／InP_（0．7）Sb_（0．3）热电子晶体管的电流增益及最高收集极电压

分析ＩｎＡｓ／ＩｎＰ（０．７）Ｓｂ（０．３）热电子晶体管的电流增益β及最高收集极电压Ｖ（ＣＭ）。计算结果表明，β超过２０，Ｖ（ＣＭ）接近１．５Ｖ。     

高性能掺杂PZT热释电陶瓷研究

对Ｐｂ＿（０．９９）Ｂｉ＿（０．０１）（Ｚｒ＿（０．９４）Ｔｉ＿（０．０６））Ｏ＿３和Ｐｂ＿（０．９９）Ｂｉ＿（０．０１）（Ｚｒ＿（０．６１）Ｔｉ＿（０．３９））Ｏ＿３两种主配方掺入Ｍｎ、Ｎｂ、Ｃｏ、Ｎｉ、ｗ等元素，制备出宽光谱吸收、电性能优良的掺杂ＰＺＴ热释电陶瓷。对其进行了结构分析和电性能测量，第一种配方的典型电学参数为：ε＿ｒ＝２１９；ｔｇδ＝０．００７８（２０℃，１ｋＨｚ）；ｐ＝４．４３×１０￣（－８）ｃ／ｃｍ￣２·Ｋ。     

Pb（WO4）0.9（MoO4）0.1晶体的生长及闪烁性能研究

以０．１ｍｏｌＭｏＯ３取代ＰｂＷＯ４中ＷＯ３生长Ｐｂ（ＷＯ４）０．９（ＭｏＯ４）０．１晶体。测试了晶体的密度、透射率和闪烁性能。克服了ＰｂＷＯ４晶体在生长中出现的开裂。生长出质量优良的Ｐｂ（ＷＯ４）０．９（ＭｏＯ４）０．１晶体。     

弯波导吸收区结构1．3μm InGaAsP／InP超辐射发光二极管的设计

本文用束传播方法（ＢＰＭ）设计了具有弯曲波导吸收区结构１．３μｍＩｎＧａＡｓＰ／ＩｎＰ超辐射发光二极管（ＳＬＤ），分析了不同吸收区长度Ｌａ和弯曲的曲率半径Ｒ对ＳＬＤ特性的影响，给出了直观的结果，并进行了优化设计。在假定吸收区后端面反射率为１，和忽略吸收区内的吸收损耗的条件下，取ｄ＝０．２μｍ，ｗ＝２μｍ，Ｌｐ＝４００μｍ，Ｌａ＝２００μｍ，Ｒ＝５００μｍ，Ｉ＝２００ｍＡ，经吸收区反射耦合回有源区内的光与有源区前端面入射光的强度比率仅为９．５×１０－３。     

Nb_2O_5掺杂对PMN－PZT系压电陶瓷电性能的影响

从晶体结构和微观组织入手，分析并讨论了掺Ｎｂ２Ｏ５量对３７．５Ｐｂ（Ｍｇ，Ｎｂ）Ｏ３－２５ＰｂＺｒＯ３－３７．５ＰｂＴｉＯ３材料的介电、压电性能的影响行为和影响机制。实验结果表明，当Ｎｂ２Ｏ５的添加量（摩尔比）ｒ（Ｎｂ２Ｏ５）＝１％时，材料有最好的压电性能（ｋｐ＝０．６２，εｒ＝４０００）。     

β－BBO晶体压电应变系数的测量

用干涉法和准静态ｄ_（３３）测量仪相结合测量了β－ＢａＢ_２Ｏ_４（β－ＢＢＯ）晶体的全部压电应变系数，结果为：ｄ_（３３）＝１．０×１０~（１２）Ｃ／Ｎ，ｄ_（３１）＝－０．８３×１０~（１２）Ｃ／Ｎ，ｄ_（２２）＝２．２×１０~（１２）Ｃ／Ｎ，ｄ_（１５）＝２１．２×１０~（１２）Ｃ／Ｎ。     

Nb2O5掺杂对ZnO压敏电阻器电性能的影响

本文研究了Ｎｂ＿２Ｏ＿５掺杂以及Ｎｂ＿２Ｏ＿５与ＺｎＯ煅烧对ＺｎＯ压敏电阻器电性能的影响。实验表明，Ｎｂ＿２Ｏ＿５的掺入使压敏电场减少，当Ｎｂ＿２Ｏ＿５含量为０．１％ｍｏｌ时，其压敏电场最小．非线性系数最大。煅烧温度越高，压敏电场越高，非线性系数越大。     

无绳电话用声表面波滤波器

本文讨论了研制的两种无绳电话机用声表面波滤波器，中心频率为４６．５７ＭＨｚ和４９．９ＭＨｚ；△ｆ＿（－３ｄＢ）＝１．７ＭＨＺ；插损≤１０ｄＢ；△ｆ＿（－４０ｄＢ）／△ｆ＿（－３ｄＢ）≤３．５；阻带抑制≤－４０ｄＢ。采用了低插损的三换能器结构。输入叉指换能器采用了波阵面均匀的孔径加权和相位加权，减小了变迹损耗。理论计算与实验结果一致。     

CATV光纤传输系统设计及维护

ＣＡＴＶ光纤传输系统设计及维护马伟宪ｍ为光调制深度，Ｒ为光电转换系数，Ｐ＿ｉ为接收光功率，Ｒ＿Ｌ为输入阻抗，ｋ为玻尔兹曼常数，Ｔ为绝对温度，Ｆ为放大器的噪声系数，Ｂ为带宽。如：一台６ｍＷ的光发射机，ｍ＝４．５％，光纤衰减０．３４ｄＢ／ｋｍ，Ｒ＝０．９...     

声表面波大带宽滤波器的设计

报道在Ｙ旋１２７．８６°Ｘ传ＬｉＮｂＯ＿３基片上采用１／８λ＿０，５／８λ＿０结构的切指加权换能器的声表面波滤波器，成功地研制了中心频率为４０ＭＨｚ，３ｄＢ带宽为２０ＭＨｚ，矩形系数（Δｆ＿４０ｄＢ／Δｆ＿３ｄＢ）为１．４８，带内波动＜１．２ｄＢ，带外抑制＞４０ｄＢ．插入损耗＜３８ｄＢ，相对带宽（Δｆ＿－３ｄＢ／ｆ＿０）大于５０％的滤波器。     

AFM observation of OMVPE grown ErP on InP (0 0 1), (1 1 1)A and (1 1 1)B substrates

ErP has been grown on InP (0 0 1), (1 1 1)A and (1 1 1)B substrates by low-pressure organometallic vapor-phase epitaxy. The morphological change with growth temperature has been explored by atomic force microscope. On all the substrates, ErP is grown in island structure. Height and area size of the ErP islands on (1 1 1)A substrate exhibit an obvious dependence on growth temperature. ErP islands grown at 540°C, that is the suitable temperature for ErP formation, gather to step edges to make wires.     

Solid phase epitaxial growth of Dy-germanide films on Ge(0 0 1) substrates

Dy thin films are grown on Ge(0 0 1) substrates by molecular beam deposition at room temperature. Subsequently, the Dy film is annealed at different temperatures for the growth of a Dy-germanide film. Structural, morphological and electrical properties of the Dy-germanide film are investigated by in situ reflection high-energy electron diffraction, and ex situ X-ray diffraction, atomic force microscopy and resistivity measurements. Reflection high-energy electron diffraction patterns and X-ray diffraction spectra show that the room temperature growth of the Dy film is disordered and there is a transition at a temperature of 300-330 °C from a disordered to an epitaxial growth of a Dy-germanide film by solid phase epitaxy. The high quality Dy₃Ge₅ film crystalline structure is formed and identified as an orthorhombic phase with smooth surface in the annealing temperature range of 330-550 °C. But at a temperature of 600 °C, the smooth surface of the Dy₃Ge₅ film changes to a rough surface with a lot of pits due to the reactions further.     

Convex corners undercutting and rhombus compensation in KOH with and without IPA solution on (1 1 0) silicon

The present investigation introduces convex corners undercutting and results of rhombus compensation patterns in 40% aqueous KOH solution and in KOH saturated with isopropanol (IPA) solution. All experiments are carried out on (1 1 0) silicon at 70 °C. Undercuts take place on convex corners in both solutions. Moreover, the front etch planes governing undercut vary with solutions. Rhombus compensations are used to correct the undercut. Perfect acute corner without residue is obtained, and there are only some residue structures on both sides of obtuse convex corners in KOH with IPA solution, which are better results than those in pure aqueous KOH solution.     

InAs／InP_（0．7）Sb_（0．3）热电子晶体管的f_T及f_（max）

用电荷控制及热电子弹道运动模型计算ＩｎＡｓ／ＩｎＰ０．７Ｓｂ０．３热电子晶体管的截止频率ｆＴ及最高振荡频率ｆｍａｘ。结果表明，ｆＴ、ｆｍａｘ分别达到２８０ＧＨｚ及６００ＧＨｚ。并指出，通过生长ＧａＳｂ中间层，ＩｎＡｓ／ＩｎＰ０．７Ｓｂ０．３ＨＥＴ可在ＧａＡｓ衬底上实现单片集成。     

Capacitance-voltage analysis of InAs quantum dots grown on InAlAs/InP(0 0 1)

The electronic properties of InAs quantum dots (QDs) grown on InAlAs/InP(0 0 1) were studied by using capacitance-voltage (C-V) analysis and photoluminescence (PL) measurements. The level positions of electrons and holes could be studied separately by using n- and p-type InAlAs matrices, respectively. The holes are found to be more confined than electrons in these kinds of dots.     

0-3型压电复合材料圆柱形水听器

使用0-3型PZT/P(VDF-TFE)压电复合材料研制出一种圆柱形水听器,对水听器的结构、材料以及灵敏度进行了理论分析,测量了水听器样品灵敏度随频率的变化曲线。研究结果表明,利用0-3型PZT/P(VDF-TFE)压电复合材料可制作出灵敏度高达-202.3 dB ref.1V/μPa的水听器,静态电容量较大,制作工艺简单,实际测量值和理论计算值很相近。     

阶梯波导TE01^d-TE0n^d模式变换器的设计与测试

介绍了一种设计简单、加工方便的TE01^d-TE0n^d模式变换器的设计计算方法，实际制作了TE01^d模到TE02^d，TE03^d，TE04^d模的三种变换器并进行了测试，测试结果表明，这种变换器实用可行，可以在微波工程领域实际应用。     

非线性参量对扬声器谐振频率f0的影响

讨论了扬声器谐振频率f0测试的不确定性,对f0测试标准进行了解读,从非线性角度分析了扬声器谐振频率波动的根本原因,并给出了正确的测试方法。     

Stability of Frenkel pairs in Si(1 0 0) surface in the presence of germanium and oxygen atoms

A first-principles pseudo-potential study of Frenkel pair generation close to the Si(1 0 0) surface in the presence of germanium and oxygen atoms is reported. The energies and structures of the defect structures (i.e. vacancy and relaxed tetrahedral Si interstitial) are calculated using supercell with up to 88 atoms. We present results obtained using the generalized gradient approximation (GGA) for the exchange-correlation energy. We examine the effect of the presence of germanium and oxygen atoms on the stability of Frenkel pairs generated near the Si(1 0 0) surface by comparing a number of individual cases, starting from vacancy interstitial pairs situated at various positions. The general tendency of the created interstitials is to climb towards the surface, but they generally remain in subsurface layers, ready to migrate into the layer. This tendency is enhanced by the presence of the Ge and/or O atoms. We show that the formation energy is lower and Si interstitials can be created with energies as low as 1.5 eV.     

Growth and fabrication of AlGaN/GaN HEMT based on Si(1 1 1) substrates by MOCVD

AlGaN/GaN high electron mobility transistor (HEMT) hetero-structures were grown on the 2-in Si (1 1 1) substrate using metal-organic chemical vapor deposition (MOCVD). Low-temperature (LT) AlN layers were inserted to relieve the tension stress during the growth of GaN epilayers. The grown AlGaN/GaN HEMT samples exhibited a maximum crack-free area of 8 mm×5 mm, XRD GaN (0 0 0 2) full-width at half-maximum (FWHM) of 661 arcsec and surface roughness of 0.377 nm. The device with a gate length of 1.4 μm and a gate width of 60 μm demonstrated maximum drain current density of 304 mA/mm, transconductance of 124 mS/mm and reverse gate leakage current of 0.76 μA/mm at the gate voltage of −10 V.