Browsing by Author "PAN, FM"

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A COMPREHENSIVE STUDY OF SUPPRESSION OF BORON PENETRATION BY AMORPHOUS-SI GATE IN P+-GATE PMOS DEVICES
(1995-12-01)
LIN, CY
;
JUAN, KC
;
CHANG, CY
;
PAN, FM
;
CHOU, PF
This paper presents a comprehensive study of the impact of the silicon gate structure on the suppression of boron penetration in p(+)-gate devices, The characteristics and reliability for different gate structures (poly-Si, alpha-Si, poly-Si/poly-Si, poly-Si/alpha-Si, alpha-Si/poly-Si, and alpha-Si/alpha-Si) in p(+) polygate PMOS devices are investigated in detail, The suppression of boron penetration by the nitrided gate oxide is also discussed, The comparison is based on flatband voltage shift as well as the value of charge to breakdown. Results show that the effect of boron diffusion through the thin gate oxide in p(+) polygate PMOS devices can be significantly suppressed by employing the as-deposited amorphous silicon gate, Stacked structures can also be employed to suppress boron penetration at the expense of higher polygate resistance, The single layer as-deposited amorphous silicon is a suitable silicon gate material in the p(+)-gate PMOS device for future dual-gate CMOS process, In addition, by employing a long time annealing at 600 degrees C prior to p(+)-gate ion implantation and activation, further improvements in suppression of boron penetration, polygate resistance, and gate oxide reliability can be achieved for the as-deposited amorphous-Si gate, Modifying the silicon gate structure instead of the gate dielectrics is an effective approach to suppress the boron penetration effect.
DIAMOND FILM GROWTH ON CEMENTED TUNGSTEN CARBIDES STUDIED BY SEM, AES AND XPS
(1992-11-23)
CHEN, JL
;
HUANG, TH
;
PAN, FM
;
KUO, CT
;
CHANG, CS
Diamond films were deposited on cemented WC substrates using a hot filament chemical vapor deposition (CVD) system with a mixture of CH4 and H-2 as the source gases. The effect of the surface pretreatments of scratching the surface and etching to remove the surface Co from the substrate on diamond nucleation and growth was studied. The effect of CH4 Concentration on diamond growth was also examined. Scanning electron microscopy, Auger electron, X-ray photoelectron and energy dispersive spectroscopies were used to examine the film morphology, quality and compositions. The results show that a good diamond-crystal quality can be obtained by reducing the surface Co content in the substrate to below 1%. Co in the surface layer of the substrate inhibits both diamond nucleation and growth. Polishing and etching treatments to scratch the surface and to remove the surface Co of the substrates are essential to maintain the surface roughness in an appropriate range to obtain diamond films with a good quality and adhesion. A change in CH4 Concentration in the source gases from 0.5 to 0.15% can change the preferred orientation of the diamond films fro m the {100} to the {111} plane.
EFFECT OF OXYGEN IMPURITY ON MICROSTRUCTURE AND BORON PENETRATION IN A BF2+ IMPLANTED LPCVD STACKED AMORPHOUS-SILICON P(+) GATED PMOS CAPACITOR
(1995-07-01)
LIN, CY
;
PAN, FM
;
CHOU, PF
;
CHANG, CY
;
電控工程研究所
Secondary ion mass spectroscopy (SIMS) and transmission electron microscopy have been used to characterize microstructure and boron penetration in BF2+ implanted amorphous silicon p(+) gated metal oxide semiconductor (PMOS) capacitors, in which oxygen is inadvertently introduced in the gate area during the low pressure chemical vapor deposition (LPCVD) process. Oxygen impurity is found to be incorporated in the LPCVD deposited amorphous silicon film by SIMS. During the break between the two successive depositions for the stacked amorphous silicon (SAS) gate, an ultrathin oxide layer is formed at the interface between the two LPCVD amorphous silicon layers. The two thinner layers lead to smaller grains in the SAS structure. The interfacial oxide layer is a diffusion barrier for oxygen, which causes a higher oxygen concentration and, in turn, retards the crystallization in the SAS structure. Both the interfacial oxide layer and the gate oxide can dissolve a significant amount of fluorine after annealihg. Reduction of free fluorine near or in the gate oxide due to fluorine dissolution in the interfacial oxide layer plays a crucial role for suppressing the boron penetration in the SAS capacitor.
EFFECTS OF DRY-ETCHING DAMAGE REMOVAL ON LOW-TEMPERATURE SILICON SELECTIVE EPITAXIAL-GROWTH
(1995-10-01)
TSENG, HC
;
CHANG, CY
;
PAN, FM
;
CHEN, LP
;
電子工程學系及電子研究所
The epitaxial silicon layer selectively grown on the reactive ion etched (RIE) silicon substrate using CF4, CHF3 and Ar etching gases has been studied. Defects and contaminants induced by the RIE process result in a rough epilayer, and degrade the current-voltage (I-V) characteristics. An interfacial carbide layer is present between the epilayer and the RIE treated substrate. Using an efficient and convenient after-etching treatment with a CF4/O-2 low-energy plasma, we obtain a clean Si surface in the patterned oxide windows for selective epitaxial growth, and the electrical characteristics are significantly improved. (C) 1995 American Institute of Physics.
EFFECTS OF DRY-ETCHING DAMAGE REMOVAL ON LOW-TEMPERATURE SILICON SELECTIVE EPITAXIAL-GROWTH
(1995-10-01)
TSENG, HC
;
CHANG, CY
;
PAN, FM
;
CHEN, LP
;
電子工程學系及電子研究所
The epitaxial silicon layer selectively grown on the reactive ion etched (RIE) silicon substrate using CF4, CHF3 and Ar etching gases has been studied. Defects and contaminants induced by the RIE process result in a rough epilayer, and degrade the current-voltage (I-V) characteristics. An interfacial carbide layer is present between the epilayer and the RIE treated substrate. Using an efficient and convenient after-etching treatment with a CF4/O-2 low-energy plasma, we obtain a clean Si surface in the patterned oxide windows for selective epitaxial growth, and the electrical characteristics are significantly improved. (C) 1995 American Institute of Physics.
SE-DOPED GAN FILMS GROWN BY LOW-PRESSURE METALORGANIC CHEMICAL-VAPOR-DEPOSITION
(1995-10-01)
GUO, JD
;
FENG, MS
;
PAN, FM
;
材料科學與工程學系
;
電子工程學系及電子研究所
Se-doped GaN films are grown for the first time by low-pressure metalorganic chemical vapor deposition (LP-MOCVD), in which H2Se is used as the Se source sas. Effects of Se doping on electrical properties of GaN films are reported. Se atoms tend to out-diffuse to the surface of the GaN film at high tempi rature. The N atomic percentage is influenced by the incorporation of H2Se in the MOCVD process. The carrier concentration was found to be significantly affected by the surface defects which develop at high H2Se dosages. The highest free electron concentration obtained is about 1.5 x 10(18) cm(-3). Increasing the growth temperature from 1000 degrees C to 1050 degrees C reduces the maximum carrier concentration to about 7x10(17) cm(-3).
STUDY OF SCHOTTKY BARRIERS ON N-TYPE GAN GROWN BY LOW-PRESSURE METALORGANIC CHEMICAL-VAPOR-DEPOSITION
(1995-10-30)
GUO, JD
;
FENG, MS
;
GUO, RJ
;
PAN, FM
;
CHANG, CY
Schottky barriers on n-type GaN films grown by low-pressure metalorganic chemical vapor deposition are characterized and derived. A thin Pt or a Pd layer is deposited by electron-gun evaporation to form Schottky contacts in a vacuum below 1X10(-6) Torr. The Schottky barrier heights of Pt on the n-GaN film are determined to be 1.04 and 1.03 eV by current-voltage (C-V) and current density-temperature (J-T) measurements, respectively. Also based on C-V and J-T measurements, the measured barrier height of Pd on n-GaN is 0.94 and 0.91 eV, respectively Schottky characteristics of Pt and Pd observed in the experiment are compared with those of Au and Ti in previous reports. (C) 1995 American Institute of Physics.
STUDY OF SCHOTTKY BARRIERS ON N-TYPE GAN GROWN BY LOW-PRESSURE METALORGANIC CHEMICAL-VAPOR-DEPOSITION
(1995-10-30)
GUO, JD
;
FENG, MS
;
GUO, RJ
;
PAN, FM
;
CHANG, CY
Schottky barriers on n-type GaN films grown by low-pressure metalorganic chemical vapor deposition are characterized and derived. A thin Pt or a Pd layer is deposited by electron-gun evaporation to form Schottky contacts in a vacuum below 1X10(-6) Torr. The Schottky barrier heights of Pt on the n-GaN film are determined to be 1.04 and 1.03 eV by current-voltage (C-V) and current density-temperature (J-T) measurements, respectively. Also based on C-V and J-T measurements, the measured barrier height of Pd on n-GaN is 0.94 and 0.91 eV, respectively Schottky characteristics of Pt and Pd observed in the experiment are compared with those of Au and Ti in previous reports. (C) 1995 American Institute of Physics.