Browsing by Author "Wang, Ying-Lang"

Now showing 1 - 20 of 45

A Novel Synthesis of a CuInSe2 Thin Film from Electrodeposited Cu-Se-In-Se Precursors with Three Steps Annealing
(2012-09-01)
Hu, Shao-Yu
;
Lee, Wen-Hsi
;
Chang, Shih-Chieh
;
Wang, Ying-Lang
;
照明與能源光電研究所
In this study, copper indium diselenide (CIS) films were synthesized from electrodeposited Cu-Se In Se precursors by three step annealing. The Se layer between Cu and In layer was grown to prevent the formation of Cu/In compound. The Cu Se precursors were first annealed to grow uniform and conductive Cu2Se surface. After deposition of the four layers precursors, two steps annealing was employed to form Cu2Se-In2Se3 precursors. Transforming Cu2Se-In2Se3 to CIS required less thermal energy. Therefore, high quality CIS film can be synthesized by two steps annealing due to its high crystallinity. The properties of the CIS films were characterized by scanning electron microscopy (SEM), X-ray Diffraction (XRD), and Raman Spectra.
A Study of Trimethylsilane (3MS) and Tetramethylsilane (4MS) Based alpha-SiCN:H/alpha-SiCO:H Diffusion Barrier Films
(2012-03-01)
Chen, Sheng-Wen
;
Wang, Yu-Sheng
;
Hu, Shao-Yu
;
Lee, Wen-Hsi
;
Chi, Chieh-Cheng
Amorphous nitrogen-doped silicon carbide (alpha-SiCN:H) films have been used as a Cu penetration diffusion barrier and interconnect etch stop layer in the below 90-nanometer ultra-large scale integration (ULSI) manufacturing technology. In this study, the etching stop layers were deposited by using trimethylsilane (3MS) or tetramethylsilane (4MS) with ammonia by plasma-enhanced chemical vapor deposition (PECVD) followed by a procedure for tetra-ethoxyl silane (TEOS) oxide. The depth profile of Cu distribution examined by second ion mass spectroscopy (SIMs) showed that 3MS alpha-SiCN:H exhibited a better barrier performance than the 4MS film, which was revealed by the Cu signal. The FTIR spectra also showed the intensity of Si-CH3 stretch mode in the alpha-SiCN:H film deposited by 3MS was higher than that deposited by 4MS. A novel multi structure of oxygen-doped silicon carbide (SiC:O) substituted TEOS oxide capped on 4MS alpha-SiC:N film was also examined. In addition to this, the new multi etch stop layers can be deposited together with the same tool which can thus eliminate the effect of the vacuum break and accompanying environmental contamination.
A Study on the Diffuse Mechanism and the Barrier Property of Copper Manganese Alloy on Tantalum
(2015-05-01)
Su, Ying-Sen
;
Lee, Wen-Hsi
;
Chang, Shih-Chieh
;
Wang, Ying-Lang
;
照明與能源光電研究所
In this paper, the electrical and material properties of CuMn/silicon oxide (SiO2) and CuMn/tantalum (Ta)/SiO2 were investigated, and an optimized concentration of Mn in the CuMn alloy as barrier layers in these two structures was also determined. CuMn alloy (0 similar to 10 atomic % Mn) deposited on SiO2 and Ta were used in this paper. A diffusion barrier layer self-formed at the interface during annealing, and the growth behavior was found to follow a logarithmic rate law. The microstructures of the CuMn films were analyzed by transmission electron microscopy and could be correlated with the electrical properties of the CuMn films. After thermal treatment, only Cu-5 at.% Mn/ SiO2 successfully avoided the diffusion of Cu atoms. Thermal stability of the films grown on Ta/SiO2 was found to be better than that on SiO2. When a Ta layer was added, the Mn atoms diffused not only to the interface, but also to the grain boundaries in the Ta layer and the interface between Ta and SiO2. This phenomenon could be explained by the surface energy. As the thickness of CuMn shrunk from 150 to 50 nm and the sample was covered with a 100-nm-thick Cu layer, the amount of Mn atoms increased at the interface of CuMn/Ta. This is because the Cu layer had higher chemical potential which induced the Mn atoms to move toward the Ta layer and reduced the amount of Mn atoms in Cu after heat treatment.
A Study on the Plating and Wetting Ability of Ruthenium-Tungsten Multi-layers for Advanced Cu Metallization
(2016-01-01)
Kuo, Tai-Chen
;
Su, Yin-Hsien
;
Lee, Wen-Hsi
;
Liao, Wei-Hsiang
;
Wang, Yu-Sheng
In this study, the plating and wetting ability of Cu/Ruthenium-Tungsten (RuW)/silicon oxide (SiO2) multi-layer stacks were investigated. RuW alloy films were prepared on a SiO2 layer by sputtering, followed by a deposition of a Cu thin film by electroplating. Scanning electron microscopy (SEM) top view images shows that Cu films can be electroplated on RuW, with smaller Cu nuclei size but in a more highly concentrated and uniform distribution than Cu films electroplated on Ta or TaN. The rate of Cu nucleation decreases and larger Cu clusters were formed on the RuW alloy films with increasing W content. Cu/RuW/SiO2 samples were annealed at 400 degrees C for 30 min and then characterized using SEM. There were fewer pin holes on the surface of a pure Cu/Ru stack compared to Cu/RuW multilayers. Cu/RuW/SiO2 multi-layers had fewer pin holes than Cu/Ta/SiO2 structures processed under similar conditions. The wetting angle, measured by SEM, of Cu on a RuW substrate (43 degrees) was still lower than that of Cu on a Ta substrate (123 degrees), which suggests that the adhesion strength of Cu onto RuW alloy is better than that onto Ta.
A study on the plating and wetting ability of ruthenium-tungsten multi-layers for advanced Cu metallization
(2016-08-16)
Kuo, Tai-Chen
;
Su, Yin-Hsien
;
Lee, Wen-Hsi
;
Liao, Wei-Hsiang
;
Wang, Yu-Sheng
In this study, the plating and wetting ability of Cu/Ruthenium-Tungsten (RuW)/silicon oxide (SiO2) multi-layer stacks were investigated. RuW alloy films were prepared on a SiO2 layer by sputtering, followed by a deposition of a Cu thin film by electro-plating. Scanning electron microscopy (SEM) top view images shows that Cu films can be electroplated on RuW, with smaller Cu nuclei size but in a more highly concentrated and uniform distribution than Cu films electroplated on Ta or TaN. The rate of Cu nucleation decreases and larger Cu clusters were formed on the RuW alloy films with increasing W content. Cu/RuW/SiO2 samples were annealed at 400 degrees C for 30 min and then characterized using SEM. There were fewer pin holes on the surface of a pure Cu/Ru stack compared to Cu/RuW multilayers. Cu/RuW/SiO2 multi -layers had fewer pin holes than Cu/Ta/SiO2 structures processed under similar conditions. The wetting angle, measured by SEM, of Cu on a RuW substrate (43) was still lower than that of Cu on a Ta substrate (123 degrees), which suggests that the adhesion strength of Cu onto RuW alloy is better than that onto Ta. Preliminary studies of Cu diffusion through 25 nm RuW layers at 650 degrees C showed no Cu penetration into the underlying Si in a Cu/RuW/Si multi-layer test structure. (C) 2016 Elsevier B.V. All rights reserved.
An electroplating method for copper plane twin boundary manufacturing
(2013-10-01)
Wang, Yu-Sheng
;
Lee, Wen-Hsi
;
Chang, Shih-Chieh
;
Nian, Jun-Nan
;
Wang, Ying-Lang
A twin boundary is a special kind of grain boundary that plays an important role in the deformation process of nanocrystalline metals, as it may affect the migration of atoms and electrons in polycrystalline solids, resulting in different electrical and mechanical properties. In this study, plane twin structures were introduced into an electroplated copper film by an electroplating method that inserts an interlayer film with a very small current density (<3 mA/cm(2)). It was found that the small-current interlayer formed a demarcation line for copper grain growth, and enhanced the twin boundaries by self-annealing at room temperature. Based on this, a method was developed to manufacture multi-plane twin boundaries to improve electron migration. Transmission electron microscopy, focused ion beam analysis, and secondary ion mass spectrometry were employed to examine this interesting phenomenon. (C) 2013 Elsevier B. V. All rights reserved.
Asymmetric Carrier Conduction Mechanism by Tip Electric Field in WSiOX Resistance Switching Device
(2012-03-01)
Syu, Yong-En
;
Chang, Ting-Chang
;
Tsai, Tsung-Ming
;
Chang, Geng-Wei
;
Chang, Kuan-Chang
Resistance random access memory (RRAM) is a great potential candidate for next-generation nonvolatile memory due to the outstanding memory characteristic. However, the resistance switching mechanism is still a riddle nowadays. In this letter, the switching mechanism is investigated by current-voltage (I-V) curve fitting in the TiN/WSiOX/Pt RRAM device. The asymmetric phenomenon of the carrier conduction behavior is explained at the high-resistance state in high electric field. The switching behavior is regarded to tip electric field by localizing the filament between the interface of top electrode and insulator.
Atomic-level quantized reaction of HfOx memristor
(2013-04-29)
Syu, Yong-En
;
Chang, Ting-Chang
;
Lou, Jyun-Hao
;
Tsai, Tsung-Ming
;
Chang, Kuan-Chang
In this study, we have observed dynamic switching behaviors in a memristive device. There are only a few atoms in the resistive switching reaction which enables the high-speed resistive switching characteristics, which was analyzed dynamically by real-time analyzing tools. From fundamental conductance considerations, the resistance of the conductive path in HfOx memristor is found to be due to barriers which are atomically incremented during the RESET process. Simultaneously, we have demonstrated the quantized switching phenomena at ultra-cryogenic temperature (4 K), which are attributed to the atomic-level reaction in metallic filament. (C) 2013 AIP Publishing LLC.
Cleaning methodology of small residue defect with surfactant in copper chemical mechanical polishing post-cleaning
(2016-11-01)
Wei, Kuo-Hsiu
;
Hung, Chi-Cheng
;
Wang, Yu-Sheng
;
Liu, Chuan-Pu
;
Chen, Kei-Wei
Advanced semiconductor manufacturing technology has adopted an alkaline solution for copper (Cu) corrosion prevention instead of the traditional acidic solution in the post-cleaning process of copper chemical mechanical polishing. Low particle and residue removal efficiency has been an issue for this process. In this study, we investigated the formation of small residue defects and the cleaning mechanism to remove these defects. The results show it is insufficient to remove the small residue defects by using the traditional process parameter tuning. Adding some friction between the pad and the wafer surface allowed the defects to be effectively reduced. (C) 2016 Elsevier B.V. All rights reserved.
Cleaning methodology of small residue defect with surfactant in copper chemical mechanical polishing post-cleaning
(2016-11-01)
Wei, Kuo-Hsiu
;
Hung, Chi-Cheng
;
Wang, Yu-Sheng
;
Liu, Chuan-Pu
;
Chen, Kei-Wei
Advanced semiconductor manufacturing technology has adopted an alkaline solution for copper (Cu) corrosion prevention instead of the traditional acidic solution in the post-cleaning process of copper chemical mechanical polishing. Low particle and residue removal efficiency has been an issue for this process. In this study, we investigated the formation of small residue defects and the cleaning mechanism to remove these defects. The results show it is insufficient to remove the small residue defects by using the traditional process parameter tuning. Adding some friction between the pad and the wafer surface allowed the defects to be effectively reduced. (C) 2016 Elsevier B.V. All rights reserved.
Effect of Annealing on the Microstructure and Electrical Property of RuN Thin Films
(2011)
Wu, Chia-Yang
;
Lee, Wen-Hsi
;
Chang, Shih-Chieh
;
Cheng, Yi-Lung
;
Wang, Ying-Lang
Ruthenium (Ru) and ruthenium nitride (RuN) thin films have been investigated as candidates for barrier layers in copper (Cu) damascene processes. In order to study the thermal stability of the Ru and RuN films, the as-deposited films were annealed by rapid thermal annealing (RTA), and the film resistance was real-time measured by a four-point probe, which was embedded in the RTA tool. The X-ray diffraction data show that the grain size of Ru decreased with the increase of the nitrogen (N) content. The Ru phases gradually changed to the RuN phases, and the resistivity of the RuN films decreased with annealing time due to nitrogen effusion. Discontinuous RuN films were found when the annealing temperature was higher than 800 degrees C and then caused a poor Cu diffusion barrier property. We also demonstrated that the Cu film could be directly electroplated on the RuN films with adequate adhesion. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3537825] All rights reserved.
Effect of bis-(3-sodiumsulfopropyl disulfide) byproducts on copper defects after chemical mechanical polishing
(2008-01-01)
Hung, Chi-Cheng
;
Lee, Wen-Hsi
;
Hu, Shao-Yu
;
Chang, Shih-Chieh
;
Chen, Kei-Wei
In the semiconductor metallization process, the superior gap-fill capability of copper (Cu) electroplating is mainly due to external additives, such as bis-(3-sodiumsulfopropyl disulfide) (SPS), which is used as an accelerator. This study demonstrates that the byproducts of SPS induced Cu defects after a chemical-mechanical-polishing (CMP) process. In conventional cyclic-voltammetric-stripping analysis, the byproducts generated from organic additives are very difficult to quantify. In this study, the authors used mass-spectrum analysis to quantify SPS byproducts and found that the SPS byproduct, 1,3-propanedisulfonic acid, correlated with the formation of Cu defects because it influenced the properties of electroplated Cu films and the chemical corrosion rate, then induced defects after the CMP process. (C) 2008 American Vacuum Society.
Effect of Cu-Ion Concentration in Concentrated H(3)PO(4) Electrolyte on Cu Electrochemical Mechanical Planarization
(2010-01-01)
Kung, Te-Ming
;
Liu, Chuan-Pu
;
Chang, Shih-Chieh
;
Chen, Kei-Wei
;
Wang, Ying-Lang
The influence of Cu-ion concentration in a concentrated H(3)PO(4) electrolyte on the Cu removal rate and planarization efficiency (PE) of electrochemical mechanical planarization (ECMP) was investigated. With increasing Cu-ion concentration in the electrolyte, results show that the Cu removal rate significantly decreased because more Cu ions in the electrolyte facilitated the formation of a surface passive film. Electrochemical analysis shows that the current density decreased from 91 to 62 mA/cm(2) when the Cu-ion concentration was increased from 35.8 to 158.6 mM. In a low Cu-ion concentration electrolyte, Cu(OH)(2) is dominant, while in a high Cu-ion concentration electrolyte, CuO predominates. A high Cu-ion concentration in the electrolyte during ECMP promotes the formation of CuO, which retards Cu-ion diffusion from the Cu surface to the electrolyte solution, resulting in a decrease in the Cu removal rate. The intensity ratio of CuO/[Cu(OH)(2)+CuO] in the Cu 2p(3/2) X-ray photoelectron spectroscopy spectrum increased from 22.1 to 85.6% when the Cu-ion concentration was increased. The effect of Cu-ion concentration on the microscale PE of Cu ECMP is discussed. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3425807] All rights reserved.
Effect of Cu-Ion Concentration in Concentrated H3PO4 Electrolyte on Cu Electrochemical Mechanical Planarization
(2010-01-01)
Kung, Te-Ming
;
Liu, Chuan-Pu
;
Chang, Shih-Chieh
;
Chen, Kei-Wei
;
Wang, Ying-Lang
The influence of Cu-ion concentration in a concentrated H3PO4 electrolyte on the Cu removal rate and planarization efficiency (PE) of electrochemical mechanical planarization (ECMP) was investigated. With increasing Cu-ion concentration in the electrolyte, results show that the Cu removal rate significantly decreased because more Cu ions in the electrolyte facilitated the formation of a surface passive film. Electrochemical analysis shows that the current density decreased from 91 to 62 mA/cm(2) when the Cu-ion concentration was increased from 35.8 to 158.6 mM. In a low Cu-ion concentration electrolyte, Cu(OH)(2) is dominant, while in a high Cu-ion concentration electrolyte, CuO predominates. A high Cu-ion concentration in the electrolyte during ECMP promotes the formation of CuO, which retards Cu-ion diffusion from the Cu surface to the electrolyte solution, resulting in a decrease in the Cu removal rate. The intensity ratio of CuO/[Cu(OH)(2)+CuO] in the Cu 2p(3/2) X-ray photoelectron spectroscopy spectrum increased from 22.1 to 85.6% when the Cu-ion concentration was increased. The effect of Cu-ion concentration on the microscale PE of Cu ECMP is discussed. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3425807] All rights reserved.
Effect of Electric Potential and Mechanical Force on Copper Electro-Chemical Mechanical Planarization
(2012-03-01)
Chen, Sheng-Wen
;
Kung, Te-Ming
;
Liu, Chuan-Pu
;
Chang, Shih-Chieh
;
Cheng, Yi-Lung
In this study, the dependence of Cu electrochemical mechanical planarization (ECMP) rate on electric potential and mechanical force in electrolyte is investigated using potentiodynamic analysis, electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS). In chemical etching, CMP, electropolishing, and ECMP processes, the Cu removal rate is mainly affected by the interplay between electric potential and mechanical force. An equivalent circuit is built by fitting the EIS results to explain the behavior of Cu dissolution and Cu passive film. The Cu dissolution rate increased with decreasing charge-transfer time-delay. The resistance of the Cu passive film (R-p) is proportional to the intensity ratio of Cu2O/[Cu(OH)(2) + CuO]. (C) 2012 The Japan Society of Applied Physics
Effect of Electrolyte Composition on Cu Stripping of Pt Contact Pins in Semiconductor Cu Electroplating Process
(2011-11-01)
Hu, Shao-Yu
;
Lee, Wen-Hsi
;
Chang, Shih-Chieh
;
Wang, Ying-Lang
;
照明與能源光電研究所
In Cu electroplating processes, the wet-contact pins are deposited with Cu films. The Pt contact pins should be stripped to remove extra Cu films to maintain contact quality and plating efficiency. However, the stripping behavior is affected by electrolyte composition. The proportion of copper sulphate and sulfuric acid changes the conductivity, pH, and cupric-ion concentration of the electrolyte solution. In this study, an electrochemistry analysis system is employed to characterize the behavior of the Pt stripping process in electrolytes having various electrolyte proportions. It was found that increasing the copper sulphate and sulfuric acid concentrations suppresses the Cu stripping current but enhances the water electrolysis reaction on the Pt surface. Copper sulphate decreased the rate of oxide dissolution and cupric diffusion. The dissolution rate was limited by denser cation layer. Sulfuric acid decreased the dissolubility of cupric ions and suppressed the electrode from releasing more cupric ions. There is no significant influence of additives such as leveler suppressor on the stripping. Minute quantity of HNO3 and H3PO4 were also added to the plating electrolyte. The additional acid HNO3 eliminated the inhibition form dense cupric layer and enhanced the stripping performance without changing the quality of the deposited films during the plating process.
Effect of N(2)/H(2) plasma treatment on the moisture adsorption of MOCVD-TiN films
(2011-05-31)
Huang, J. K.
;
Huang, Cheng-Liang
;
Chang, Shih-Chieh
;
Cheng, Yi-Lung
;
Wang, Ying-Lang
In the application of contact glue layer for semiconductor devices, a nitrogen/hydrogen (N(2)/H(2)) plasma treatment is usually used to reduce the amount of C and O impurities of metallorganic chemical vapor deposition titanium nitride (MOCVD-TiN) films. This study found that the sheet resistance of as-deposited MOCVD-TiN film without N(2)/H(2) plasma treatment dramatically increased with exposure time due to moisture adsorption. Increasing plasma treatment power and time was able to retard the increase in sheet resistance. From residue gas analysis at 200 degrees C, it was found that the amount of H(2)O outgases from the MOCVD-TiN films decreased with increasing plasma treatment power and time. TEM images reveal that the surface of the MOCVD-TiN films became compact as it received more plasma treatment energy, making it difficult for the external moisture to diffuse into and react with the MOCVD-TiN films. (C) 2011 Elsevier B.V. All rights reserved.
Effect of N-2/H-2 plasma treatment on the moisture adsorption of MOCVD-TiN films
(2011-05-31)
Huang, J. K.
;
Huang, Cheng-Liang
;
Chang, Shih-Chieh
;
Cheng, Yi-Lung
;
Wang, Ying-Lang
In the application of contact glue layer for semiconductor devices, a nitrogen/hydrogen (N-2/H-2) plasma treatment is usually used to reduce the amount of C and O impurities of metallorganic chemical vapor deposition titanium nitride (MOCVD-TiN) films. This study found that the sheet resistance of as-deposited MOCVD-TiN film without N-2/H-2 plasma treatment dramatically increased with exposure time due to moisture adsorption. Increasing plasma treatment power and time was able to retard the increase in sheet resistance. From residue gas analysis at 200 degrees C, it was found that the amount of H2O outgases from the MOCVD-TiN films decreased with increasing plasma treatment power and time. TEM images reveal that the surface of the MOCVD-TiN films became compact as it received more plasma treatment energy, making it difficult for the external moisture to diffuse into and react with the MOCVD-TiN films. (C) 2011 Elsevier B.V. All rights reserved.
Effect of polyimide baking on bump resistance in flip-chip solder joints
(2014-03-01)
Cheng, Hsi-Kuei
;
Feng, Shien-Ping
;
Lai, Yi-Jen
;
Liu, Kuo-Chio
;
Wang, Ying-Lang
The effect of polyimide (PI) thermal process on the bump resistance of flip-chip solder joint is investigated for 28 nm technology device with aggressive extreme low-k (ELK) dielectric film scheme and lead-free solder. Kelvin structure is designed in the bump array to measure the resistance of single solder bump. An additional low-temperature pre-baking before standard PI curing increases the bump resistance from 9.3 m Omega to 225 m Omega. The bump resistance increment is well explained by a PI outgassing model established based on the results of Gas Chromatography-Mass Spectrophotometer (GC-MS) analysis. The PI outgassing substances re-deposit on the Al bump pad, increasing the resistance of interface between under-bump metallurgy (UBM) and underneath Al pad. The resistance of interface is twenty-times higher than pure solder bump, which dominates the measured value of bump resistance. Low-temperature plasma etching prior to UBM deposition is proposed to retard the PI outgassing, and it effectively reduces the bump resistance from 225 m Omega to 10.8 m Omega. (C) 2013 Published by Elsevier Ltd.
Effect of tungsten incorporation in cobalt tungsten alloys as seedless diffusion barrier materials
(2017-03-05)
Su, Yin-Hsien
;
Kuo, Tai-Chen
;
Lee, Wen-Hsi
;
Wang, Yu-Sheng
;
Hung, Chi-Cheng
With the increase in the aspect ratio of the interconnect features in integrated circuits, the direct electroplating of Cu on diffusion barrier without sputtered Cu seed layers is attracting more and more attention. In this study, direct electroplating of Cu onto sputtered CoW films with various W concentration in acidic CuSO4 solution is investigated. Also, the adhesion and anti-diffusion properties of the CoW thin films for Cu are explored. The results show that Cu films cannot be electrodeposited on thin Co layers due to corrosion of Co in the acidic bath. For CoW alloys, higher W concentration is found to be beneficial for suppressing corrosion of CoW films and also improving the thermal stability. However, on the surface of Cu/CoW films with high W concentration, Cu agglomeration and pin-holes were found after annealing, indicating poor adhesion between Cu and high W-content CoW alloys. In this study, CoW alloys with moderate W concentration around 50% are found to be a direct platable material which also demonstrates desirable adhesion and anti-diffusion characteristics for Cu interconnects application. (C) 2017 Elsevier B.V. All rights reserved.