• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.49 no.1
• /
• pp.8-14
• /
• 2012

The device performances of n-channel MuGFET with different fin numbers and fin widths but the total effective channel width is constant have been characterized. Two kinds of Pi-gate devices with fin number=16, fin width=55nm, and fin number=14, fin width=80nm have been used in characterization. The threshold voltage, effective electron mobility, threshold voltage roll-off, inverse subthreshold slope, PBTI, hot carrier degradation, and drain breakdown voltage have been characterized. From the measured results, the short channel effects have been reduced for narrow fin width and large fin numbers. PBTI degradation was more significant in devices with large fin number and narrow fin width but hot carrier degradation was similar for both devices. The drain breakdown voltage was higher for devices with narrow fin width and large fin numbers. With considering the short channel effects and device degradation, the devices with narrow fin width and large fin numbers are desirable in the device layout of MuGFETs.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.25 no.1
• /
• pp.1-8
• /
• 2001

Performance of a rectangular fin is investigated by a three dimensional analytical method. Heat loss and the temperature obtained from the three dimensional analysis are compared with those calculated from a two dimensional analysis. Fin effectiveness, fin resistance and fin efficiency for the rectangular fin are presented as a function of non-dimensional fin length and fin width. The results are obtained in the following : (1) heat loss calculated from the two dimensional analysis is the same as that obtained from the three dimensional analysis with adiabatic boundary condition in z-direction, (2) heat loss obtained from the two dimensional analysis approaches the value for the three dimensional analysis as the non-dimensional fin width becomes large, (3) fin effectiveness increases as non-dimensional fin length increases and non-dimensional fin width decreases, and vice versa for fin efficiency.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.10 no.6
• /
• pp.743-752
• /
• 1998

Experiments were performed to characterize single-phase heat transfer behavior of submerged liquid jet with multiple nozzle normally impinging on the smooth and extended surfaces. Arrays of 9 and 36 nozzles were used, with diameters of 0.5 to 2.0mm providing nozzle area ratio (AR) from 0.05 to 0.2. The square pin fin arrays were chosen as extended surfaces and the effects of geometrical parameters such as fin height, the ratio of fin width to channel width on heat transfer enhancement were examined. Single nozzle characteristics were also evaluated for comparison. The results clearly showed that heat transfer enhancement could be realized by using multiple nozzles at the constant volume flow rate. The average Nusselt number of multiple nozzle impingement on the smooth surface was correlated by the following equation : Nu/$Pr\frac{1}{3}=0.94 Re^{0.56}N^{-0.12}AR^{0.50}$The average heat transfer coefficients of multiple nozzle impingement on the extended surfaces decreased with increasing fin height and the ratio of fin width to channel width. The effectiveness of ex-tended surfaces ranged from 1.5 to 3.5 depending on the fin height, the ratio of fin width to channel width of pin fin arrays, nozzle number and nozzle area ratio.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.1
• /
• pp.135-141
• /
• 2014

In this paper, the device design guideline to reduce the threshold voltage variation with fin width in junctionless MuGFET has been suggested. It has been observed that the threshold voltage variation was increased with increase of fin width in junctionless MuGFETs. To reduce the threshold voltage variation with fin width in junctionless MuGFETs, 3-dimensional device simulation with different gate dielectric materials, silicon film thickness, and an optimized fin number has been performed. The simulation results showed that the threshold voltage variation can be reduced by the gate dielectric materials with a high dielectric constant such as $La_2O_3$ and the silicon film with ultra-thin thickness even though the fin width is increased. Particularly, the reduction of the threshold voltage variation and the subthreshold slope by reducing the fin width and increasing the fin numbers is known the optimized device design guideline in junctionless MuGFETs.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.749-752
• /
• 2014

The device performance of n-channel MuGFET with different fin width, existence of spacer and channel length has been characterized. Tri-Gate structure(fin number=10) has been used. There are four kinds of Tri-Gate with fin width=55nm with spacer, fin width=70nm with spacer, fin width=55nm without spacer, fin width=70nm without spacer. DIBL, subthreshold swing, Vt roll-off, (above Short Channel Effect)and hot carrier stress degradation have been measured. From the experiment results, short Channel Effect with spacer was decreased, hot carrier degradation with spacer and narrow fin width was decreased. Therefore, layout of LDD structure with spacer and narrow fin width is desirable in short channel effect and hot carrier degradation.

• Journal of Industrial Technology
• /
• v.21 no.A
• /
• pp.33-40
• /
• 2001

Heat loss from the trapezoidal fins haying different upper side slope and that from a rectangular fin are investigated by the three dimensional analytic method. It is shown that the trapezoidal fins having different upper side slope become an approximate rectangular fin by inst adjusting the slope factor. The comparison of the heat loss between a rectangular fin and an approximate rectangular fin is represented as a function of the non-dimensional fin length, fin width and Biot number to make sure that the analysis on the trapezoidal fins having different upper side slope is countable. One of the results is that the relative value of heat loss between a rectangular fin and an approximate rectangular fin is less than 1.5% for given ranges of non-dimensional length and width in case of Bi = 0.1.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.28 no.5
• /
• pp.195-201
• /
• 2016

Enhanced tubes are widely used in air-conditioning and process industries. Structural tubes having three-dimensional roughness are well known to be able to significantly enhance pool boiling heat transfer of refrigerants. In this study, five structural enhanced tubes having different fin density, fin height, and fin gap width were tested using R-134a. Results showed that the heat transfer coefficient was increased with increased fin density. Within test range, the effect of fin height on pool boiling heat transfer coefficient was insignificant. The heat transfer coefficients of the optimum configuration (2047 fpm, 0.21 mm gap width) tube were lower than those of other commercial enhanced tubes. This might be due to the larger fin gap width of the present enhanced tube.

• International Journal of Air-Conditioning and Refrigeration
• /
• v.9 no.2
• /
• pp.94-101
• /
• 2001

Fin effectiveness and efficiency of a thermally asymmetric rectangular fin are represented as a function of non-dimensional fin length, width, fip tip surface Biot number and the ratio of fin bottom surface Biot number to top surface Biot number. For this analysis, three dimensional separation of variables method is used. One of the results shows that fin effectiveness can be increased or decreased depending on the fin length as the fin tip surface Biot number increases while fin efficiency decreases without depending on that as the fin tip surface Biot number increases.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.8 no.2
• /
• pp.156-163
• /
• 2008

We proposed a new $p^+/n^+$ gate locally-separated-channel (LSC) bulk FinFET which has vertically formed oxide region in the center of fin body, and device characteristics were optimized and compared with that of normal channel (NC) FinFET. Key device characteristics were investigated by changing length of $n^+$ poly-Si gate ($L_s$), the material filling the trench, and the width and length of the trench at a given gate length ($L_g$). Using 3-dimensional simulations, we confirmed that short-channel effects were properly suppressed although the fin width was the same as that of NC device. The LSC device having the trench non-overlapped with the source/drain diffusion region showed excellent $I_{off}$ suitable for sub-50 nm DRAM cell transistors. Design of the LSC devices were performed to get reasonable $L_s/L_g$ and channel fin width ($W_{cfin}$) at given $L_gs$ of 30 nm, 40 nm, and 50 nm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.23 no.9
• /
• pp.676-680
• /
• 2010

In this paper, Fin-type silicon-oxide-nitride-oxide-silicon (SONOS) flash memory are fabricated and the electrical characteristics are analyzed. Compared to the planar-type SONOS devices, Fin-type SONOS devices show good short channel effect (SCE) immunity due to the enhanced gate controllability. In memory characteristics such as program/erase speed, endurance and data retention, Fin-type SONOS flash memory are also superior to those of conventional planar-type. In addition, Fin-type SONOS device shows improved SCE immunity in accordance with the decrease of Fin width. This is known to be due to the fully depleted mode operation as the Fin width decreases. In Fin-type, however, the memory characteristic improvement is not shown in narrower Fin width. This is thought to be caused by the Fin structure where the electric field of Fin top can interference with the Fin side electric field and be lowered.