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SiGe HBT is a key device for BiCMOS process used for high-speed communication, automotive radar and defense military. For normal SiGe process, the control of emitter window undercut is often not easy. In this paper, we studied the influence of emitter undercut on HBT parameters, through both TCAD simulation and wafer results. While transistors with larger area-to-perimeter ratio are supposed to have greater current gain, it is found in our research that with the increase of this ratio along with increasing undercut, the gain decreased. The process mechanism of this gain decrease is discussed and the influences on other parameters such as cut-off frequency have also been studied in this work. It is found in our study that when the undercut increased over 100%, the device parameters changed no more than 10%. Therefore, although the emitter undercut is hard to be avoided in a given process, it can be controlled, and the influence of fluctuation is acceptable.

We report a novel type of RF component using two-terminal III-Nitride heterostructure varactor with capacitively-coupled contacts (C3) which can be used as a RF switch as well as a power limiter(PL) or other control device type. This C3 varactor consists of two electrodes deposited on top of an AIGaN/GaN heterostructure forming capacitors between the electrode and the 2DEG channel. C3 electrodes allow for efficient RF signal injection into the 2DEG channel with low equivalent impedance at high frequencies. The C3 varactor has simple planar structure fully compatible with MMICs. The GaN C3 varactors have significant advantages over GaN heterostructure field-effect transistors (HFETs) as they allow for shorter channel, do not have gates or ohmic contacts and hence the fabrication is alignment- and anneal - free, they do not consume DC current and provide the DC block. The fabricated SPST C3 switch exhibits 0.8 dB insertion loss and 27 dB isolation at 18 GHz. The maximum switching power extrapolated from 2 GHz data is around 38 dBm. The fabricated varactor PLs show 0.2-0.7 dB loss and limiting powers in the range from 17 to 40 dBm. The C3 PL shows superior performance compared to other known types, e.g. Schottky diode PLs. The fabricated C3 PLs and switches showed the output power variations within 0.5 dB during 100 hours 24 dBm CW stress. They also demonstrated as low as 0.5 dB loss degradation at 2000 C as compared to the room temperature performance.

The objectives of this study were to analyses whether hospital ownership and hospital process orientation have a role on volume flexibility, and to discuss the implications of these relationships. A questionnaire was developed and sent to a random sample of 300 hospital departments in Shanghai. The response rate was 57%. The data were analyzed with confirmatory factor analysis and structural equation modeling in LISREL. The results indicate that the model with relationships between hospital ownership, hospital process orientation and volume flexibility was found to be a reasonable representation of volume determining mechanism at hospital departments (p = 0.095, indicating no significant differences between the model and the data set). Ownership correlated strongly with process orientation (0.72) and volume flexibility (0.60). Given ownership, process orientation also correlated with volume flexibility (0.20).

This research mainly examines the factors that affect an employee's occupational commitment. Respondents of the questionnaire were all insurance agents, and a total of 246 valid questionnaires were completed. After going through correlation and regression analysis of the collected data, it is implied that insurance agents' affective occupational commitment, is higher than their affective organizational commitment. Also, their organizational commitment is positively correlated to their occupational commitment. Meanwhile, the agents' affective occupational commitment is also positively influenced by their job satisfaction. On the other hand, the respondents' job satisfaction has a positive effect on their affective organizational commitment.

Innovation counts very much? has been discussed more that thirty years. Most scholars consider innovation one of the cores in modern management and strategy. There have been many empirical studies on organizational innovation from viewpoint of organizational culture. And some studies focus on that from organizational structure. This study discusses over the relationships among organizational culture, structure, learning, and innovation. The samples in the study come from fourteen financial holding companies in Taiwan. The findings are presented in the study. Organizational culture has significantly positive impact on organizational learning and innovation. Organizational learning has significantly positive influence on organizational innovation.

A 16 Mb 1TIC FeRAM with a novel cell structure has been successfully developed with 0.25 /spl mu/m process technology using (Bi,La)/sub 4/Ti/sub 3/O/sub 12/ (BLT) capacitors for the first time. The developed FeRAM is highly scalable and reliable as a result of applying an MTP (merged top electrode and plate line) structure and BLT stacked capacitor, respectively.

A new algorithm for the design of linear edge slot arrays is presented. The main feature is the theoretical consideration of mutual couplings between slot apertures. Based upon the characteristics of the computed mutual impedance between edge slots and the theoretical admittance of an isolated slot in the waveguide with zero wall thickness, the phase of the mutual impedance and the absolute ratio of mutual impedance to self impedance in realistic condition are reasonably assumed. Under this assumption, the design curve of isolated slot admittances and incremental conductances are interpolated from the measured reflection coefficients of 12 test sections. Thus a linear array can be achieved by recursively choosing a set of slot inclinations and depths and comparing the computed active admittances of these slots with the desired coupling coefficients. An example of designing a Ka band linear edge slot array with -30 dB SLL Taylor's distribution is presented to show the validity of this algorithm. >