Browsing by Author "Chiang, Cheng-Neng"

Now showing 1 - 4 of 4

Enhancement of NiSi-Based Nanocrystal Formation by Incorporating Ge Elements for Nonvolatile Memory Devices
(2009)
Hu, Chih-Wei
;
Chang, Ting-Chang
;
Tu, Chun-Hao
;
Chiang, Cheng-Neng
;
Lin, Chao-Cheng
In this work, a NiSiGe mixed film was deposited by the cosputtering approach. The rapidly thermal treatment condition was executed at 600 degrees C for 30 s in nitrogen ambient to form the nanocrystal structure. From the results of the transmission electron microscopy, the annealed NiSiGe film reveals a larger nanocrystal size and density distribution than pure NiSi. X-ray photoelectron spectroscopy analyses were used to confirm that the Ge elements provide the additional nucleation centers and enhance the nanocrystal formation during the thermal process. Raman spectroscopy and an energy-dispersive spectrometer also exhibit the compositions of nanocrystals including Ni, Si, and Ge elements. With the better formation process, a remarkable improvement of memory effect is observed by comparing with the NiSi and NiSiGe nanocrystal memory devices. Also, the NiSiGe nanocrystal device shows a better retention characteristic due to the lower quantum confinement effect.
Formation of the distributed NiSiGe nanocrystals nonvolatile memory formed by rapidly annealing in N(2) and O(2) ambient
(2010-10-01)
Hu, Chih-Wei
;
Chang, Ting-Chang
;
Tu, Chun-Hao
;
Chiang, Cheng-Neng
;
Lin, Chao-Cheng
In this work, electrical characteristics of the Ge-incorporated Nickel silicide (NiSiGe) nanocrystals memory device formed by the rapidly thermal annealing in N(2) and O(2) ambient have been studied. The trapping layer was deposited by co-sputtering the NiSi(2) and Ge, simultaneously. Transmission electron microscope results indicate that the NiSiGe nanocrystals were formed obviously in both the samples. The memory devices show obvious charge-storage ability under capacitance-voltage measurement. However, it is found that the NiSiGe nanocrystals device formed by annealing in N(2) ambient has smaller memory window and better retention characteristics than in O(2) ambient. Then, related material analyses were used to confirm that the oxidized Ge elements affect the charge-storage sites and the electrical performance of the NCs memory. (C) 2010 Elsevier B.V. All rights reserved.
Formation of the distributed NiSiGe nanocrystals nonvolatile memory formed by rapidly annealing in N-2 and O-2 ambient
(2010-10-01)
Hu, Chih-Wei
;
Chang, Ting-Chang
;
Tu, Chun-Hao
;
Chiang, Cheng-Neng
;
Lin, Chao-Cheng
In this work, electrical characteristics of the Ge-incorporated Nickel silicide (NiSiGe) nanocrystals memory device formed by the rapidly thermal annealing in N-2 and O-2 ambient have been studied. The trapping layer was deposited by co-sputtering the NiSi2 and Ge, simultaneously. Transmission electron microscope results indicate that the NiSiGe nanocrystals were formed obviously in both the samples. The memory devices show obvious charge-storage ability under capacitance-voltage measurement. However, it is found that the NiSiGe nanocrystals device formed by annealing in N-2 ambient has smaller memory window and better retention characteristics than in O-2 ambient. Then, related material analyses were used to confirm that the oxidized Ge elements affect the charge-storage sites and the electrical performance of the NCs memory. (C) 2010 Elsevier B.V. All rights reserved.
NiSiGe nanocrystals for nonvolatile memory devices
(2009-02-09)
Hu, Chih-Wei
;
Chang, Ting-
;
Tu, Chun-Hao
;
Chiang, Cheng-Neng
;
Lin, Chao-Cheng
In this work, charge-storage characteristics of NiSiGe nanocrystal memory device have been studied. Transmission electron microscope shows that the annealed NiSiGe film has higher nanocrystal size and density distribution. Related material analyses such as x-ray photoelectron spectroscopy, Raman spectroscopy, and energy dispersive spectrometer were used to confirm that the Ge elements provide the additional nucleation centers and enhance the nanocrystals aggregation during thermal process. With the improved nanocrystal formation process, a remarkable improvement of the memory effect is observed by comparing the NiSi and NiSiGe nanocrystals. In addition, the retention characteristics of the nanocrystals memory devices have been discussed.