Browsing by Author "Hsieh, IJ"

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Characterization and fabrication of chimney-shaped metal field emitters
(1996-01-01)
Cheng, HC
;
Wang, CC
;
Ku, TK
;
Hsieh, IJ
;
電子工程學系及電子研究所
A novel fabrication technology has been successully developed for chimney-shaped metal field emitters in order to improve the electrical characterisitcs of field-emission devices. This technology is based on anisotropic dry etching and sputtering deposition of metal film as well as wet etching of the attached silicon. It enables easy fabrication of chimney-shaped field emitters with excellent uniformity and high reproducibility. The anode current of the chimney-shaped Cr field emitter array (FEA) is 36.3 mu-A at the applied voltage of 1100 V and the threshold voltage V-T, defined as that for which the anode current I-n reaches 1 mu-A is 787 V. The chimney-shaped Cr FEA emits a current thirty times higher than that from the cone-shaped Cr-clad FEA at the applied voltage of 1100 V. This can be attributed to the presence of many sharp tips along the edge of the chimney-shaped emitter. The degradation phenomenon is not observed because compensation occurs between these many sharp tips. Another merit of this technique is that only one photolithography mask is needed during processing.
Cu contamination effect in oxynitride gate dielectrics
(2001-11-01)
Lin, YH
;
Pan, FM
;
Liao, YC
;
Chen, YC
;
Hsieh, IJ
We have studied the effect of Cu contamination in oxynitride gate dielectrics. Compared to thermal SiO2 with a physical thickness of 3-5 nm, the oxynitride shows a much improved Cu contamination resistance. Furthermore, the Cu contamination resistance increases with increasing nitrogen content. The mechanism of improved gate dielectric resistance to Cu is due to the strong diffusion barrier properties of oxynitride as observed by secondary ion mass spectroscopy. (C) 2001 The Electrochemical Society.
Enhanced electron emission from phosphorous- and boron-doped diamond-clad Si field emitter arrays
(1996-12-15)
Ku, TK
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Chen, SH
;
Yang, CD
;
She, NJ
;
Tarntair, FG
A new fabrication technology of polycrystalline diamond-clad Si microtips using microwave plasma chemical vapor deposition (MPCVD) has been developed to improve the characteristics of electron field emission from the pure Si tips. A uniform and smooth coating morphology for the diamond-clad Si tips have been achieved. Electron emission currents of diamond-clad tips are much higher than those of pure Si tips. Such great improvement is attributed to the lowering of the effective work function in the diamond-clad tips. The effects of phosphorus- and boron-doped diamond-clad Si tips have been also studied in comparison with the undoped ones. The current-voltage characteristics of the undoped diamond-clad tips were further enhanced by the in-situ doping of phosphorus or boron due to a higher electron supplement. Moreover, the P-doped diamond-clad tips show a better field emission performance as compared to the B-doped ones. This difference is surmised to be associated with the higher electron conductivity and defect densities of P-doped diamond films.
Enhanced electron emission from phosphorus-doped diamond-clad silicon field emitter arrays
(1996-05-01)
Ku, TK
;
Chen, SH
;
Yang, CD
;
She, NJ
;
Wang, CC
Undoped and phosphorus (P)-doped diamond-clad Si field emitter arrays have been successfully fabricated using microwave plasma chemical vapor deposition (MPCVD) technology. The electron emission from the blunt diamond-clad microtips are much higher than those for the pure Si tips with sharp curvature due to a lower work function, Furthermore, the characteristics of emission current against applied voltage for the P-doped diamond-clad tips show superior emission at lower field to the undoped ones, After the examination of Auger electron spectroscopy (AES) and electrical characteristics of as-grown diamond, such a significant enhancement of the electron emission from the P-doped diamond-clad tips is attributed to a higher electron conductivity and defect densities.
Fabrication and characterization of diamond-clad silicon field emitter arrays
(1995-12-01)
Cheng, HC
;
Ku, TK
;
Hsieh, BB
;
Chen, SH
;
Leu, SY
Microsized silicon tip arrays with sharp curvature were formed based on the techniques including reactive ion etching and oxidation-sbarpening. A new fabrication technology of polycrystalline diamond-clad Si microtips using microwave plasma CVD(MPCVD) was subsequently developed to improve the capability and stability of the field emission from the pure Si tips. By means of SEM and transmission electron microscopy (TEM), the as-deposited films are found to be polycrystalline diamond with fine grain (similar to 800 Angstrom) structure. With the anode voltage of 1100V and anode-to-cathode distance of 30 mu m, the emission current of 240 mu A in a 50 x 50 diamond-clad Si microtip array can be achieved, which is much higher than those for Cr-clad and pure Si microtip arrays. Based on curve fitting of a Fowler-Nordheim (F-N) plot, such great improvement is partially attributed to the lowering of the effective work function from 5.5 eV to 2.08 eV.
Fabrication and characterization of gated Si field emitter arrays with gate aperture below 0.5 mu m
(1995)
Ku, TK
;
Hsieh, BB
;
Chen, MS
;
Wang, CC
;
Wang, PW
Fabrication and characterization of the Pd-silicided emitters for field-emission devices
(1995)
Wang, CC
;
Ku, TK
;
Feng, MS
;
Hsieh, IJ
;
Cheng, HC
Fabrication and characterization of the Pd-silicided emitters for field-emission devices
(1996-06-01)
Wang, CC
;
Ku, TK
;
Hsieh, IJ
;
Cheng, HC
;
電子工程學系及電子研究所
The structure of Pd-silicided held emitters based on the silicon micromachining technology has been demonstrated. The uniform and extremely sharp silicided emitters are formed using wet chemical etching, low-temperature oxidation sharpening (LTOS), metal coating, and furnace annealing. The silicided emitters are firstly identified by the bright-held, dark-held images, and diffraction patterns of transmission electron microscope (TEM). Under the applied voltage of 1100 V, the anode currents of the Pd-coated and silicided emitters are 16 mu A and 26 mu A, respectively. The values of threshold voltage V-T for Pd-coated and silicided emitters are about 745 V and 785 V, respectively. The lower threshold voltage of the Pd-coated emitters is duo to the smaller emission work function of palladium. The emission work function of the Pd-silicided emitters is calculated to be 8.31 eV. Furthermore; the long and short-term current stabilities of silicided emitters is also better than that of Pd-coated ones. These results show that these silicided emitters have potential applications in vacuum microelectronics to obtain superior Lifetime, reliability, and stability.
Fabrication and characterization of the Pd-silicided emitters for field-emission devices
(1996-06-01)
Wang, CC
;
Ku, TK
;
Hsieh, IJ
;
Cheng, HC
;
電子工程學系及電子研究所
The structure of Pd-silicided held emitters based on the silicon micromachining technology has been demonstrated. The uniform and extremely sharp silicided emitters are formed using wet chemical etching, low-temperature oxidation sharpening (LTOS), metal coating, and furnace annealing. The silicided emitters are firstly identified by the bright-held, dark-held images, and diffraction patterns of transmission electron microscope (TEM). Under the applied voltage of 1100 V, the anode currents of the Pd-coated and silicided emitters are 16 mu A and 26 mu A, respectively. The values of threshold voltage V-T for Pd-coated and silicided emitters are about 745 V and 785 V, respectively. The lower threshold voltage of the Pd-coated emitters is duo to the smaller emission work function of palladium. The emission work function of the Pd-silicided emitters is calculated to be 8.31 eV. Furthermore; the long and short-term current stabilities of silicided emitters is also better than that of Pd-coated ones. These results show that these silicided emitters have potential applications in vacuum microelectronics to obtain superior Lifetime, reliability, and stability.
Fabrication and characterization of various carbon-clad silicon microtips with ultra-small tip radii.
(1996)
Ku, TK
;
Chen, SH
;
Yang, CD
;
She, NJ
;
Tarntair, FG
In order to take the advantages of diamond and carbon coating on flat-panel display, unscratched sharp Si microtip arrays have been carburized based on the bias enhanced nucleation (BEN) and low-pressure MPCVD deposition to obtain an ultra-sharp carburized Si FEAs. The tip radii of these BEN-carburized Si tips can be reduced below 300 Angstrom under low deposition temperature (<550 degrees C). Furthermore, some BEN-carburized samples were further deposited by normal diamond growth conditions to form the ultra-sharp DLC-clad Si FEAs with enhanced emission ability.
Growth of MgWO4 phosphor by RF magnetron sputtering
(1998-05-01)
Chu, JP
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Hsieh, IJ
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Chen, JT
;
Feng, MS
;
材料科學與工程學系
Magnesium tungstate (MgWO4) thin film phosphors prepared by radio frequency (RF) magnetron sputter deposition were characterized. alpha- and beta-MgWO4 were determined as the major phases in the films studied. Since the deposition rates of film were influenced by RF power. working pressure as well as oxygen content, these processing parameters played an important role in affecting the phase present in the as-deposited films. It is found that the formation of alpha-MgWO4 phase was favorable for the films grown at low deposition rates (<40 Angstrom min(-1)) whereas beta-MgWO4 was a dominant phase at high deposition rates. Substrate temperatures showed no detectable effects on the deposition rates and thus the beta-MgWO4 was the only phase present for the substrate temperature range examined. A phase formation mechanism due to the deposition rate difference is described. Post-deposition annealing significantly improved the cathodoluminescence (CL) properties of films, with annealing temperatures at 750 degrees C or above being the most effective. CL property improvement appeared to he attributed to the enhancement of crystallinity and the transformation to the stable beta-MgWO4 phase during the annealing. Annealing-induced film delamination and blisters. however, resulted in deterioration of low voltage CL properties. (C) 1998 Elsevier Science S.A. All lights reserved.
Low voltage high speed SiO(2)/AlGaN/AlLaO(3)/TaN memory with good retention
(2005)
Chin, A
;
Laio, CC
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Chen, C
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Chiang, KC
;
Yu, DS
To improve trapping using deeper well AlGaN (chi=3.8eV), lower voltage drop in high-K AlLaO(3) barrier (kappa=23), and smaller erase current by large Delta E(c) of AILaO(3)/TaN, the SiO(2)/AlGaN/AlLaO(3)/TaN devices show good 85 degrees C memory integrity of low +/- 10V 1ms P/E, large 3.9V initial Delta V(th) and 2.4V extrapolated 10-year retention. A fast 100ps P/E of +/- 11V still gives 3.0V initial Delta V(th) and 1.6V 10-year retention.
The strong degradation of 30 angstrom gate oxide integrity contaminated by copper
(2001-04-01)
Lin, YH
;
Chen, YC
;
Chan, KT
;
Pan, FM
;
Hsieh, IJ
A much higher leakage current, a lower breakdown effective field, a poorer charge-to-breakdown, and worse stress-induced leakage current are observed in ultrathin 30 Angstrom oxides even at a low Cu contamination of 10 ppb. The strong degradation of the ultrathin gate oxide integrity can be explained by the tunneling barrier lowering and the increased interface trap tunneling due to the presence of Cu in the oxide and at the oxide-Si interface. (C) 2001 The Electrochemical Society.