Highly Efficient Rapid Annealing of Thin Polar Polymer Film Ferroelectric Devices at Sub‐Glass Transition Temperature

An unexpected rapid anneal of electrically active defects in an ultrathin (15.5 nm) polar polyimide film at and below glass transition temperature (T_g) is reported. The polar polymer is the gate dielectric of a thin‐film‐transistor. Gate leakage current density (J_g) through the polymer initially increases with temperature, as expected, but decreases rapidly at T_g ? 60 °C. After ≈2 min at T_g, the leakage is reduced by nearly three orders of magnitude. A concomitant observation is that the drain current (I_d)–gate voltage (V_g) hysteresis decreases with temperature, reaching zero at nearly the same temperature at which J_g collapses. As J_g drops further, the drain current hysteresis increases again but in the opposite direction. This combination strongly supports the interpretation of rapid defect annealing.     

High-speed monolithic silicon photoreceivers on high resistivityand SOI substrates

We compare monolithic silicon optical receivers fabricated on high resistivity and silicon-on-insulator (SOI) substrates. Each receiver consisted of a lateral p-i-n photodiode and an NMOS transimpedance preamplifier. At a drain voltage (V_DD) of 3.5 V, a photodiode voltage (V_PD) of 30 V, and a wavelength of 850 nm, the high resistivity receiver exhibited sensitivities of -31.9 dBm at 622 Mb/s and -23.2 dBm at the maximum operating speed of 1.0 Gb/s. At V_DD =5 V and V_PD=20 V, the sensitivity of the SOI receiver was -26.1 dBm at 622 Mb/s, -20.2 dBm at 1.0 Gb/s and -12.2 dBm at the maximum speed of 2.0 Gb/s. Single supply operation at 5 V and 3 V was also demonstrated for the SOI receiver. Methods for extending the speed and improving the sensitivity characteristics in more advanced technologies with lower supply voltages are discussed     

Breakdown probabilities for thin heterostructure avalanche photodiodes

The recurrence theory for the breakdown probability in avalanche photodiodes (APDs) is generalized to heterostructure APDs that may have multiple multiplication layers. The generalization addresses layer-boundary effects such as the initial energy of injected carriers as well as the layer-dependent profile of the dead space in the multiplication region. Reducing the width of the multiplication layer serves to both downshift and sharpen the breakdown probability curve as a function of the applied reverse-bias voltage. In structures where the injected carriers have an initial energy that is comparable to the ionization threshold energy, the transition from linear mode to Geiger-mode is more abrupt than in structures in which such initial energy is negligible. The theory is applied to two recently fabricated Al/sub 0.6/Ga/sub 0.4/As-GaAs heterostructure APDs and to other homostructure thin GaAs APDs and the predictions of the breakdown-voltage thresholds are verified.     

Non-starch polysaccharides of canola meal: Quantification,digestibility in poultry and potential benefit of dietary enzyme supplementation

The non-starch polysaccharide (NSP) content as determined by gas chromatography (component neutral sugars) and colorimetry (uronic acids) was shown to be 16–22% in ten different samples of defatted canola (low glucosinolate rapeseed) seed. The non-cellulosic components of NSP accounted for 13–16% of the meal and on average consisted of arabinose (33%), xylose (13%), galactose (13%), glucose (5%), mannose (3%), rhamnose (2%), fucose (2%) and uronic acids (30%). Yellow-seeded and brown-seeded samples of canola contained similar contents of total dietary fibre although the composition of the fibre components tended to differ with the former showing a low content of lignin and associated polyphenols and a high content of NSP as compared with the latter type. NDF values tended to be lower for yellow-seeded than for brown-seeded canola due to the relatively high content of NSP in neutral detergent solubles of yellow-seeded canola. An initial balance study with laying hens showed low (<3%) digestibility of the polysaccharide components, and further studies were conducted with a commercial enzyme preparation (SP249, Novo Laboratories Ltd, Lachine, Quebec) to enhance the in-vivo hydrolysis of the NSP fraction of the meal. Laying hens were fed a semipurified diet containing 40% commercial canola meal with and without enzyme (1%). NSP digestibility was increased to 37% by the enzyme supplementation.     

Automatic quantification of changes in bone in serial MR images of joints

Recent innovations in drug therapies have made it highly desirable to obtain sensitive biomarkers of disease progression that can be used to quantify the performance of candidate disease modifying drugs. In order to measure potential image-based biomarkers of disease progression in an experimental model of rheumatoid arthritis (RA), we present two different methods to automatically quantify changes in a bone in in-vivo serial magnetic resonance (MR) images from the model. Both methods are based on rigid and nonrigid image registration to perform the analysis. The first method uses segmentation propagation to delineate a bone from the serial MR images giving a global measure of temporal changes in bone volume. The second method uses rigid body registration to determine intensity change within a bone, and then maps these into a reference coordinate system using nonrigid registration. This gives a local measure of temporal changes in bone lesion volume. We detected significant temporal changes in local bone lesion volume in five out of eight identified candidate bone lesion regions, and significant difference in local bone lesion volume between male and female subjects in three out of eight candidate bone lesion regions. But the global bone volume was found to be fluctuating over time. Finally, we compare our findings with histology of the subjects and the manual segmentation of bone lesions.     

基矛电磁波的低流速测量中干扰因素分析研究

介绍了电磁渡测量流速的基本原理一多普勒效应．分析了影响低流速测量的主要干扰因素一发射泄漏干扰和旁瓣干扰。根据接收信号中发射泄漏干扰不变的特性,提出了去均值滤波的方法来消除干扰,对数据进行预处理;根据旁瓣干扰的信号特性,提出了通过频谱加窗和二次加权平均法构造频域带通滤波器来抑制干扰的方法,在仿真比较完各个窗函数的性能之后...     

A 2-GHz clocked AlGaAs/GaAs HBT byte-slice datapath chip

A byte-slice datapath for exploring multi-chip RISC processor development in AlGaAs-GaAs heterojunction bipolar transistor (HBT) technology has been designed, fabricated and tested. The circuits are implemented using differential current-mode logic (CML) and emitter-coupled logic (ECL) with signal swings of 250 mV. Each datapath chip contains a single slice, including an 8-bit by 32-word single-port register file with a 230-ps read access time, and an 8-bit carry-select adder with a 140-ps select path and a 380-ps ripple-carry path. Each unpackaged die was tested using an at-speed boundary scan test scheme. The register file and adder carry chain are also implemented in a special test chip for accurate performance characterization of these critical circuits     

Definition of the Geometric Area of a Microelectrode Tip by Plasma Etching of Parylene

The geometric area of the tip of an intracortical stimulation electrode can be defined by combining photoresist masking with oxygen plasma etching of Parylene.1 The method was tested with both capacitor and iridium oxide electrodes and caused no significant degradation of the electrical properties of the electrode.     

Avalanche buildup time of InP/InGaAsP/InGaAs avalanche photodiodes with separate absorption, grading, and multiplication regions

The avalanche buildup time of an avalanche photodiode can be determined from the frequency response of the noise power as a function of the dc multiplication M0. In this paper we report on the first measurements of the avalanche buildup time of InP/InGaAsP/ InGaAs avalanche photodiodes with separate absorption, grading, and multiplication regions (SAGM-APD's). Measurements on several different device structures reveal that the avalanche buildup time (gain-bandwidth product) decreases (increases) with increasing carrier concentration in the multiplication region. The shortest buildup time that we have observed wasM_{0} times 4.2ps which corresponds to a gain-bandwidth Product of 38 GHz.     

Measurement and prediction of digital radio performance on a long overwater path

The simultaneous field trial performance of 34 Mbit/s 4PSK, 2 × 34 Mbit/s 8PSK and 4 × 34 Mbit/s 16QAM digital radio systems over a 158 km overwater path in Australia is reported, and the measured outage performance is then used to derive propagation data, which in turn is used to predict performance using quadruple diversity. In addition, a generalised outage prediction technique is derived for n diversity.