Effects of Aspect Ratio of Micro-sized Photoresist Patterns on Bond Strength between a Si Substrate with AFM Fracture Observation

2008 ◽  
Vol 1139 ◽  
Author(s):  
Chiemi Ishiyama ◽  
Akinobu Shibata ◽  
Masato Sone ◽  
Yakichi Higo
Keyword(s):  
Aspect Ratio ◽  
Bond Strength ◽  
Testing Machine ◽  
Three Dimensional ◽  
Maximum Load ◽  
Initiation Site ◽  
Cylindrical Shape ◽  
Si Substrate ◽  
Cylinder Length ◽  
Loading Mode

AbstractBond strength between three dimensional micro-sized cylindrical patterns and Si substrate has been evaluated to clarify the effects of the cylinder length vs. diameter ratio, i.e. the aspect ratio, on the bond strength. Cylindrical shape was employed for avoiding ambiguity of loading point under bend conditions. Multiple cylindrical specimens of an epoxy type photoresist, SU-8 with various lengths were fabricated on a silicon substrate under the same photolithographic condition. Bond strength between micro-sized SU-8 and Si substrate under bend loading mode was measured by a mechanical testing machine for micro-sized materials. The maximum bend moment is 9.6 × 10−6 Nm in average and lineally increases with increasing the aspect ratio. On the other hand, the maximum load, i.e. maximum shear load is 106 mN in average and almost constant with increasing aspect ratio. This result suggests that the shear stress near the interface may cause the initiation of delamination. This phenomenon is discussed with three dimensional fracture observation and quantitative analysis of the line profile around the initiation site by AFM.

Development of New Evaluation Method for Adhesive Strength between Microsized Photoresist and Si Substrate of MEMS Devices

2007 ◽  
Vol 345-346 ◽  
pp. 1185-1188 ◽  
Author(s):  
Chiemi Ishiyama ◽  
Masato Sone ◽  
Yakichi Higo
Keyword(s):  
Adhesive Strength ◽  
Evaluation Method ◽  
Testing Machine ◽  
Micro Electro Mechanical System ◽  
Shear Loading ◽  
Cylindrical Shape ◽  
Mems Devices ◽  
Si Substrate ◽  
Loading Mode ◽  
Adhesive Shear Strength

An evaluation method for adhesive bending and shear strengths between microsized components and silicon substrate were developed to quantitively determine micro-sized adhesive strength for micro-electro mechanical system (MEMS) devices. Cylindrical shape is employed as a micro-sized adhesive specimen to simply analyze adhesive stresses of both shear and bending. Micro-sized adhesive tests between micro-sized SU-8 cylindrical specimen and Si substrate were performed using a mechamical testing machine for micro-sized material that has developed by our group. Delamination of all the specimens occurred within the SU-8 near by the substrate in a brittle manner under both bending and shear loading conditions. The adhesive bending stress is 57 % lower than the bend strength of the SU-8 material. The adhesive shear strength under bend loading is 15 % lower than the adhesive strength under shear loading and the delamination surface is different in each loading mode. All the results suggest that some defects at the interface must induce the stress concentration, which may make the apparent strength of SU-8 decrease.

scholarly journals Effect of Nd:YAG Laser with/without Graphite Coating on Bonding of Lithium Disilicate Glass-Ceramic to Human Dentin

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Amjad Abu Hasna ◽  
Stephanie Semmelmann ◽  
Fernanda Alves Feitosa ◽  
Danilo De Souza Andrade ◽  
Franklin R Tay ◽  
...  
Keyword(s):  
Bond Strength ◽  
Glass Ceramic ◽  
Nd:Yag Laser ◽  
Testing Machine ◽  
Glass Ceramics ◽  
Lithium Disilicate ◽  
Resin Cement ◽  
Cylindrical Shape ◽  
Universal Testing ◽  
Human Dentin

This study evaluated the effect of different surface treatments on the tensile bond strength between lithium disilicate glass-ceramics, resin cement, and dentin. Fifty truncated cone-shape glass-ceramics were divided into five groups (n = 10): G1, control: 10% hydrofluoric acid (HF); G2, Nd:YAG laser + silane; G3, Sil + Nd:YAG laser; G4, graphite + Nd:YAG laser + Sil; and G5, graphite + Sil + Nd:YAG laser. Fifty human third-molars were cut to cylindrical shape and polished to standardize the bonding surfaces. The glass-ceramic specimens were bonded to dentin with a dual-cured resin cement and stored in distilled water for 24 h at 37ºC. Tensile testing was performed on a universal testing machine (10 Kgf load cell at 1 mm/min) until failure. The bond strength values (mean ± SD) in MPa were G1 (9.4 ± 2.3), G2 (9.7 ± 2.0), G3 (6.7 ± 1.9), G4 (4.6 ± 1.1), and G5 (1.2 ± 0.3). Nd:YAG laser and HF improve the bond strength between lithium disilicate glass-ceramics, resin cement, and dentin. The application of a graphite layer prior to Nd:YAG laser irradiation negatively affects this bonding and presented inferior results.

scholarly journals Three-Dimensional Surface Evaluation and Shear Bond Strength of Three Pre-treatment E-max Surfaces for Metal and Ceramic Orthodontic Brackets

2020 ◽  
Vol 10 (2) ◽  
pp. 113-118
Author(s):  
Huda A. Mohammed ◽  
Omar S. Ali
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
Roughness Parameter ◽  
Lithium Disilicate ◽  
Maximum Load ◽  
Maximum Height ◽  
Universal Adhesive ◽  
Ceramic Brackets ◽  
Pre Treatment

3D evaluation and shear bond strength (SBS) for metal and ceramic brackets after three pre-treatment surfaces of lithium disilicate (LD) crowns. Sixty lithium disilicate (LD) crowns were fabricated in laboratory according to manufacturer instruction and then divided into six groups (three groups for metal brackets and three groups for ceramic one). The 1st group for both was treated with round diamond bur, the 2nd one by hydrofluoric acid (HFA) 9.0%, and the 3rd group by laser (Er,Cr:YSGG). All treated surfaces were examined by laser profilometer and scan electron microscope. The Scotchbond Universal Adhesive and Transbond XT were used for bracketing procedure for metal and ceramic bracket (central incisor, 0,022” slot). Universal testing machine was used for shear bond. A crosshead speed of 1 mm/min was used, and the maximum load necessary to deboned the bracket will be recorded. HFA treated surfaces gave a highest SBS for both metal and ceramic brackets, then laser and finally the bur. The lowest roughness parameter Sa (arithmetical mean height) was in bur, both laser and HFA gave no significant differences. The HFA gave a highest Sz (maximum height) and Spc (arithmetic mean peak curvature) value. To increase the shear bond strength, the HFA is one of the best methods for roughness although the laser gave nearby roughness parameters. Ceramic brackets gave higher SBS than metal one with all pre-treatment procedures.

scholarly journals Comparison of bond strength between self-adhered and conventional composites

2018 ◽  
Vol 22 (3) ◽  
Author(s):  
Adria Permana Putra ◽  
Elin Karlina ◽  
Renny Febrida
Keyword(s):  
Bond Strength ◽  
Testing Machine ◽  
Third Molar ◽  
Critical Factor ◽  
Test Method ◽  
The Self ◽  
Laboratory Research ◽  
Cylindrical Shape ◽  
Group I ◽  
Strength Difference

Bond strength towards dentine is a critical factor for composite restoration success. The purpose of this research was to obtain data on self-adhered composite bond strength to tooth dentine. This research was an experimental laboratory research that used 10 third molar teeth as samples. The teeth were prepared by thinning its mesial part until it reaches dentine layer. The sample was divided into two groups, each consisting of 5 teeth. In group I was applied self-adhered composite with Fusio® Liquid Dentine brand, whereas group II was applied conventional composite with Ivoclar Te-Econom Flow®. The applied composite had a cylindrical shape with 6 mm diameter. The sample was then placed on the test arm. The shear bond strength test method then conducted on Universal Testing Machine (UTM). Obtained data was tested using Two-tails Independent t-Test (α = 0,05). The results showed the average of self-adhered composite bond strength to dentine is 1,8878 ± 0,2859 MPa and conventional composite for 4,43552 ± 0,49472 MPa. The data showed that the self-adhered composite bond strength to dentine is smaller than conventional composite. From this research can be concluded that there was bond strength difference between the self-adhered composite with conventional composites towards the tooth dentine.

scholarly journals Comparative Study of Adhesion of Brackets with Metal Injection Molding (MIM) Technology and Welded bases: In vitro Study

2020 ◽  
Vol 14 (1) ◽  
pp. 240-246 ◽  
Author(s):  
Luis A. V. Izquierdo ◽  
Francyle S. H. Sanches ◽  
Francisco Molina ◽  
Rafael P. Henriques ◽  
Emerson F. Cruz ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Injection Molding ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
Maximum Load ◽  
Metal Injection Molding ◽  
Intergroup Comparison ◽  
Mim Technology

Introduction: Brackets bonded to enamel surface depend on the adhesion material and the quality of the bracket base. Objective: The aim of this study was to compare the shear bond strength of metallic brackets with Metal Injection Molding (MIM) technology base or welded base. Materials and Methods: Forty mandibular extracted premolars mounted in acrylic resin blocks were divided randomly into two groups, both bonded with Transbond XT. In Group 1, brackets with MIM technology bases (Masel) were used, and in group 2, brackets with a welded base (Morelli) were used. After 24 hours, all brackets were tested for shear bond strength in a universal testing machine. Intergroup comparison was performed with an independent t test. Results: MIM base brackets showed a mean maximum load registered of 107.55 N, a mean shear bond strength of 9.58 MPa with a standard deviation of 5.80 MPa and the welded base brackets showed a mean maximum load of 167.37 N, a mean shear bond strength of 13.28 MPa with a standard deviation of 2.58 MPa. The difference between the two groups was statistically significant, indicating a higher shear bond strength of the welded base brackets. Conclusion: It was concluded that the brackets with welded bases presented a significantly higher shear bond strength than the brackets with MIM bases.

scholarly journals Comparative study of the dental substrate used in shear bond strength tests

2003 ◽  
Vol 17 (2) ◽  
pp. 171-175 ◽  
Author(s):  
Murilo Baena Lopes ◽  
Mário Alexandre Coelho Sinhoreti ◽  
Lourenço Correr Sobrinho ◽  
Simonides Consani
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Statistical Difference ◽  
Testing Machine ◽  
Adhesive System ◽  
Human Tooth ◽  
Cylindrical Shape ◽  
Human Teeth ◽  
Human Enamel ◽  
Human Dentin

The purpose of this study was to compare shear bond strength values obtained in human enamel and dentin with the values obtained in bovine teeth using two adhesive systems with different actions. Forty human tooth half-crowns and forty bovine tooth crowns were flattened to a minimum plain area of 5 mm in diameter. The samples were divided in four groups of 20 specimens each: 1) human enamel; 2) bovine enamel; 3) human dentin; 4) bovine dentin. The samples of each group were divided in 2 subgroups of 10 samples each, according to the adhesive system used: 1) Scotchbond Multi-Purpose (SBMP); and 2) Clearfil Liner Bond 2V (CLB2V) applied according to the manufacturer's recommendations. Afterwards, restorations of Z100 composite with cylindrical shape (4 mm diameter x 5 mm height) were made using a metallic mold to submit the samples to shear bond testing on an Instron universal testing machine, at a crosshead speed of 0.5 mm/min. The data were submitted to ANOVA and Tukey's test (5%). In enamel, there was no statistical difference between bovine and human teeth for SBMP (7.36 MPa, human; 8.24 MPa, bovine), nor for CLB2V (10.01 MPa, human; 7.95, bovine). In dentin, SBMP showed a statistically lower mean on human dentin (7.01 MPa) than on bovine dentin (11.74 MPa). For CLB2V, there was no statistical difference between human (7.43 MPa) and bovine (9.27 MPa) substrates.

scholarly journals Storage effect on the shear bond strength of adhesive systems

2003 ◽  
Vol 14 (1) ◽  
pp. 42-47 ◽  
Author(s):  
Alysson Noriyuki Kajishima Konno ◽  
Mário Alexandre Coelho Sinhoreti ◽  
Simonides Consani ◽  
Lourenço Correr Sobrinho ◽  
Rafael Leonardo Xediek Consani
Keyword(s):  
Bond Strength ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
Storage Period ◽  
Cylindrical Shape ◽  
Adhesive Systems ◽  
Significance Level ◽  
Instron Testing Machine ◽  
Storage Times ◽  
Made In

The purpose of this study was to evaluate the effects of storage (1 day, 3 months and 6 months) on the shear bond strength of five adhesive systems on bovine dentin substrate. One hundred and fifty bovine incisors were flattened until areas of a minimum of 5 mm in diameter were exposed. A round area of 4 mm in diameter was marked on the dentin to be treated with the following adhesive systems: Clearfil Liner Bond 2V (CLB2V), Scotchbond Multi Purpose Plus (SBMP), Optibond Solo (SOLO), Prime & Bond NT (PBNT) and Etch & Prime 3.0 (E&P). To perform the test, a composite restoration (Z100) was made in a cylindrical shape on the treated surface. After the storage period in distilled water at 37ºC, the samples were tested on an Instron testing machine. Results were submitted to ANOVA and Tukey's test at 5% significance level. SBMP, PBNT and E&P were statistically similar at all storage times (p>0.05). CLB2V demonstrated the highest mean shear bond strength at 3 months which was not significantly different at 6 months (p>0.05). In addition, CLB2V had the highest means at all times tested. SOLO had the lowest mean shear bond strength at 6 months, which was statistically lower than means at 3 months and 1 day (p<0.05).

Fluorocarbon Precursor for High Aspect Ratio via Milling in Focused Ion Beam Modification of Integrated Circuits

2004 ◽  
Author(s):  
Valery Ray
Keyword(s):  
Side Effects ◽  
Aspect Ratio ◽  
Integrated Circuits ◽  
High Aspect Ratio ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Enabling Technology ◽  
Si Substrate ◽  
Ion Beam Modification ◽  
The Past

Abstract Gas Assisted Etching (GAE) is the enabling technology for High Aspect Ratio (HAR) circuit access via milling in Focused Ion Beam (FIB) circuit modification. Metal interconnect layers of microelectronic Integrated Circuits (ICs) are separated by Inter-Layer Dielectric (ILD) materials, therefore HAR vias are typically milled in dielectrics. Most of the etching precursor gases presently available for GAE of dielectrics on commercial FIB systems, such as XeF2, Cl2, etc., are also effective etch enhancers for either Si, or/and some of the metals used in ICs. Therefore use of these precursors for via milling in dielectrics may lead to unwanted side effects, especially in a backside circuit edit approach. Making contacts to the polysilicon lines with traditional GAE precursors could also be difficult, if not impossible. Some of these precursors have a tendency to produce isotropic vias, especially in Si. It has been proposed in the past to use fluorocarbon gases as precursors for the FIB milling of dielectrics. Preliminary experimental evaluation of Trifluoroacetic (Perfluoroacetic) Acid (TFA, CF3COOH) as a possible etching precursor for the HAR via milling in the application to FIB modification of ICs demonstrated that highly enhanced anisotropic milling of SiO2 in HAR vias is possible. A via with 9:1 aspect ratio was milled with accurate endpoint on Si and without apparent damage to the underlying Si substrate.

scholarly journals Electromechanically reconfigurable optical nano-kirigami

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shanshan Chen ◽  
Zhiguang Liu ◽  
Huifeng Du ◽  
Chengchun Tang ◽  
Chang-Yin Ji ◽  
...  
Keyword(s):  
Near Infrared ◽  
Large Range ◽  
Three Dimensional ◽  
High Contrast ◽  
Si Substrate ◽  
High Modulation ◽  
Gold Nanostructure ◽  
Infrared Wavelengths ◽  
On Chip ◽  
Nano Electromechanical System

AbstractKirigami, with facile and automated fashion of three-dimensional (3D) transformations, offers an unconventional approach for realizing cutting-edge optical nano-electromechanical systems. Here, we demonstrate an on-chip and electromechanically reconfigurable nano-kirigami with optical functionalities. The nano-electromechanical system is built on an Au/SiO2/Si substrate and operated via attractive electrostatic forces between the top gold nanostructure and bottom silicon substrate. Large-range nano-kirigami like 3D deformations are clearly observed and reversibly engineered, with scalable pitch size down to 0.975 μm. Broadband nonresonant and narrowband resonant optical reconfigurations are achieved at visible and near-infrared wavelengths, respectively, with a high modulation contrast up to 494%. On-chip modulation of optical helicity is further demonstrated in submicron nano-kirigami at near-infrared wavelengths. Such small-size and high-contrast reconfigurable optical nano-kirigami provides advanced methodologies and platforms for versatile on-chip manipulation of light at nanoscale.

scholarly journals Surface Texturing of Si with Periodically Arrayed Oblique Nanopillars to Achieve Antireflection

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 380
Author(s):  
Jun-Hyun Kim ◽  
Sanghyun You ◽  
Chang-Koo Kim
Keyword(s):  
Aspect Ratio ◽  
Plasma Etching ◽  
Surface Texturing ◽  
Light Reflection ◽  
Si Substrate ◽  
Weighted Mean ◽  
Optical Reflectance ◽  
Si Substrates ◽  
Aspect Ratios ◽  
Shadowing Effect

Si surfaces were texturized with periodically arrayed oblique nanopillars using slanted plasma etching, and their optical reflectance was measured. The weighted mean reflectance (Rw) of the nanopillar-arrayed Si substrate decreased monotonically with increasing angles of the nanopillars. This may have resulted from the increase in the aspect ratio of the trenches between the nanopillars at oblique angles due to the shadowing effect. When the aspect ratios of the trenches between the nanopillars at 0° (vertical) and 40° (oblique) were equal, the Rw of the Si substrates arrayed with nanopillars at 40° was lower than that at 0°. This study suggests that surface texturing of Si with oblique nanopillars reduces light reflection compared to using a conventional array of vertical nanopillars.

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