High/fmax collector-up AlGaAs/GaAsheterojunction bipolar transistors with a heavily carbon-doped basefabricated using oxygen-ion implantation

AlGaAs/GaAs collector-up heterojunction bipolar transistors (HBTs) with a heavily carbon-doped base layer were fabricated using oxygen-ion implantation and zinc diffusion. The high resistivity of the oxygen-ion-implanted AlGaAs layer in the external emitter region effectively suppressed electron injection from the emitter, allowing collector current densities to reach values above 10⁵ A/cm ². For a transistor with a 2-μm×10-μm collector, f_T was 70 GHz and f_max was as high as 128 GHz. It was demonstrated by on-wafer measurements that the first power performance of collector-up HBTs resulted in a maximum power-added efficiency of as high as 63.4% at 3 GHz     

Impact of the research training environment and counseling psychology students' Holland personality type on interest in research.

We surveyed 358 counseling psychology students in 10 APA-accredited programs with regard to change in research interest and (a) research training environment, (b) J. L. Holland (1978) personality type, and (c) environment-personality interactions. Investigative and Investigative-Artistic students had the highest interest in research. Enterprising interests were related to lower levels of research interest and delay in completing training. Programs identified in a previous study as having the greatest positive impact on research interest were found in the current study to also select students with more Investigative interests. Environment, person (Holland type), and some person–environment interactions were all predictive of increased research interest, but person variables were the strongest predictors. The most impactful specific environment factors may depend on the Holland personality type of the student. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The possibility of possibility.

Comments that B. D. Slife (see record 1995-13451-001), M. Gergen (see record 1995-14294-001), R. N. Williams (see record 1995-12851-001), and M. S. Richardson (see record 1995-14311-001) all seem to suggest that the contextless nature of the traditional conception of free will is problematic. Although each author attempts to contextualize this traditional conception, many of their explanations reveal that the underlying problem remains. It is suggested that a radically new assumption of time, such as Heidegger's temporality, is necessary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Submicrometer self-aligned AlGaAs/GaAs heterojunction bipolartransistor process suitable for digital applications

A self-aligned process is developed to obtain submicrometer high-performance AlGaAs/GaAs heterojunction bipolar transistors (HBTs) which can maintain a high current gain for emitter sizes on the order of 1 μm². The major features of the process are incorporation of an AlGaAs surface passivation structure around the entire emitter-base junction periphery to reduce surface recombination and reliable removal of base metal (Ti/W) deposits from the sidewall by electron cyclotron resonance (ECR) plasma deposition of oxide and ECR plasma etching by NF₃. A DC current gain of more than 30 can be obtained for HBTs with an emitter-base junction area of 0.5×2 μm² at submilliampere collector currents. The maximum f_T and f_max obtained from a 0.5×2 μm² emitter HBT are 46 and 42 GHz, respectively at I_C=1.5 and more than 20 GHz even at I_C=0.1 mA     

A 7-ns 140-mW 1-Mb CMOS SRAM with current sense amplifier

A 7-ns 140-mW 1-Mb CMOS SRAM was developed to provide fast access and low power dissipation by using high-speed circuits for a 3-V power supply: a current-sense amplifier and pre-output buffer. The current-sense amplifier shows three times the gain of a conventional voltage-sense amplifier and saves 60% of power dissipation while maintaining a very short sensing delay. The pre-output buffer reduces output delays by 0.5 ns to 0.75 ns. The 6.6-μm² high-density memory cell uses a parallel transistor layout and phase-shifting photolithography. The critical charge that brings about soft error in a memory cell can be drastically increased by adjusting the resistances of poly-PMOS gate electrodes. This can be done without increasing process complexity or memory cell area. The 1-Mb SRAM was fabricated using 0.3-μm CMOS quadrupole-poly and double-metal technology. The chip measures 3.96 mm×7.4 mm (29 mm²)     

Reply to Humphreys and to Jensen.

Replies to L. G. Humphrey's (see PA, Vol 56:Issue 2) and A. R. Jensen's (see PA, Vol 56:Issue 2) criticisms of the authors' study on the effects of verbal strategy training on race differences in nonverbal reasoning test performance. The authors agree with Humphrey's argument that significant interactions cannot be proven with nested designs, although it is pointed out that his suggestion that there were large numbers of low-scoring Ss in both groups who did not understand the directions is misleading, since it ignores the other low scorers who were merely inefficient problem solvers. It is also argued that Jensen's implication that demonstrations of training effects are irrelevant for conclusions about racial genetic differences or the absence of such differences is incorrect because successful training logically eliminates the possibility of genetic inabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The SDC cell-A novel design methodology for high-speed arithmeticmodules using CMOS/BiCMOS precharged circuits

The shielded dynamic complex-gate (SDC) cell is a cell-based design methodology for generating high-speed modules or macrocells using precharged circuit technology. In order to achieve ultrafast operation, a BiCMOS precharged circuit has been developed. This circuit is about 1.5 to 2.0 times faster than the conventional CMOS precharged circuit. The effect of alpha-particle injection under low-voltage operation has been studied, and CMOS/BiCMOS precharged circuits with alpha-particle-induced noise suppression have been proposed. A 32-b arithmetic and logic unit (ALU) utilizing a BiCMOS SDC cell designed and fabricated with 0.5-μm BiCMOS technology is discussed. The application of the SDC cell design to a mainframe execution unit (parallel adder) is also described     

Oxygen evolution reaction on transition metal borides

The oxygen evolution reaction on the transition metal borides (mainly Co_xB and Ni_xB) was investigated with various composition ratio of BMetal and sintering temperature. The activity of oxygen evolution reaction became maximum at the composition range of BCo =$\text{1}\text{3}$ and BNi ? $\text{1}\text{3}$, respectively. The sintering temperature also affected largely the activity of oxygen evolution reaction and the metal borides with the composition ratio BMetal = $\text{1}\text{3}$ gave the highest activity at the sintering temperature lower than 300°C for nickel borides and 400 ～ 500°C for cobalt borides. The oxygen evolution reaction on iron boride and lanthanum hexaboride was also briefly discussed, and the order of the activity of oxygen evolution reaction was as follows:

The Tafel slope of oxygen evolution reaction on metal borides was varied from ca. 40 mV for Ni (ca 70 mV for Co) to ca. 120 mV with the increase in the activity of oxygen evolution reaction. The oxide formation became easier with the increase in the activity of oxygen evolution reaction and the differential capacity of the oxide formation in the range more cathodic than the oxygen evolution increased with the decrease in the apparent activation energy of oxygen evolution reaction at 0.60 V (HgHgO).     

Combinatorial pharmacologic effects of gemcitabine and its metabolite dFdU

Recent evidence has shown that the gemcitabine metabolite, dFdU, is pharmacologically active. Though less potent, dFdU has a longer half‐life and could potentiate or antagonize the activity of gemcitabine. Hence, studies were undertaken to evaluate the combined effects. Following chemical synthesis, an improved purification procedure for dFdU was developed (80 % yield; >99 % purity). Zebrafish phenotype‐based embryo screens revealed no acute toxicity after gemcitabine or dFdU treatment. Only gemcitabine affected zebrafish development in a dose‐dependent manner. Synergy or antagonism for the combination was not observed. Antitumor effects for dFdU were dose dependent. Antagonism was tumor cell‐line dependent and did not depend on formation of the intracellular active metabolite of gemcitabine, suggesting that the drug–metabolite interaction occurs later. These studies highlight a platform for testing the pharmacologic activity for anticancer agent and metabolite combinations. Such analyses are expected to provide insight into the beneficial or harmful effect(s) of metabolites towards parent drug activity.