HfO2 Thin Film for Microelectromechanical Systems Application

2017 ◽  
pp. 699-718
Author(s):  
Bing Miao ◽  
Alton B. Horsfall
Keyword(s):  
Thin Film ◽  
Microelectromechanical Systems

Development of a High Cycle Fatigue Life Prediction Model for Thin Film Silicon Structures

2018 ◽  
Vol 140 (3) ◽  
Author(s):  
Chia-Cheng Chang ◽  
Sheng-Da Lin ◽  
Kuo-Ning Chiang
Keyword(s):  
Thin Film ◽  
Fatigue Life ◽  
Life Prediction ◽  
Microelectromechanical Systems ◽  
Fatigue Testing ◽  
Mesh Size ◽  
Prediction Equation ◽  
Frequency Effect ◽  
Element Analysis ◽  
Solution Type

The fatigue characteristics of microelectromechanical systems (MEMS) material, such as silicon or polysilicon, have become very important. Many studies have focused on this topic, but none have defined a good methodology for extracting the applied stress and predicting fatigue life accurately. In this study, a methodology was developed for the life prediction of a polysilicon microstructure under bending tests. Based on the fatigue experiments conducted by Hocheng et al. (2008, “Various Fatigue Testing of Polycrystalline Silicon Microcantilever Beam in Bending,” Jpn. J. Appl. Phys., 47, pp. 5256–5261) and (Hung and Hocheng, 2012, “Frequency Effects and Life Prediction of Polysilicon Microcantilever Beams in Bending Fatigue,” J. Micro/Nanolithogr., MEMS MOEMS, 11, p. 021206), cantilever beams with different dimensions were remodeled with mesh control technology using finite element analysis (FEA) software to extract the stress magnitude. The mesh size, anchor boundary, loading boundary, critical stress definition, and solution type were well modified to obtain more correct stress values. Based on the new stress data extracted from the modified models, the optimized stress-number of life curve (S–N curve) was obtained, and the new life-prediction equation was found to be referable for polysilicon thin film life prediction under bending loads. After comparing the literature and confirming the new models, the frequency effect was observed only for the force control type and not for the displacement control type.

Resonant Fatigue Testing of Cantilever Specimens Prepared from Thin Films

2008 ◽  
Vol 1139 ◽  
Author(s):  
Kwangsik Kwak ◽  
Masaaki Otsu ◽  
Kazuki Takashima
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Cantilever Beam ◽  
Microelectromechanical Systems ◽  
Fatigue Testing ◽  
Crystalline Silicon ◽  
Gold Foil ◽  
Fatigue Properties ◽  
Mems Devices ◽  
Testing Method

AbstractFatigue properties of thin film materials are extremely important to design durable and reliable microelectromechanical systems (MEMS) devices. However, it is rather difficult to apply conventional fatigue testing method of bulk materials to thin films. Therefore, a fatigue testing method fitted to thin film materials is required. In this investigation, we have developed a fatigue testing method that uses a resonance of cantilever type specimen prepared from thin films. Cantilever beam specimens with dimensions of 1(W) × 3(L) × 0.01(t) mm3 were prepared from Ni-P amorphous alloy thin films and gold foils. In addition, cantilever beam specimens with dimension of 3(L) × 0.3(W) × 0.005(t) mm3 were also prepared from single crystalline silicon thin films. These specimens were fixed to a holder that is connected to an golddio speaker used as an actuator, and were resonated in bending mode. In order to check the validity of this testing method, Young's moduli of these specimens were measured from resonant frequencies. The average Young's modulus of Ni-P was 108 GPa and that of gold foil specimen was 63 GPa, and these values were comparable with those measured by other techniques. This indicates that the resonance occurred theoretically-predicted manner and this testing method is valid for measuring the fatigue properties of thin films. Resonant fatigue tests were carried out for these specimens by changing amplitude range of resonance, and S-N curves were successfully obtained.

On the Effect of Water-Induced Degradation of Thin-Film Piezoelectric Microelectromechanical Systems

2020 ◽  
pp. 1-11
Author(s):  
Runar Plunnecke Dahl-Hansen ◽  
Frode Tyholdt ◽  
Jo Gjessing ◽  
Andreas Vogl ◽  
Paul Wittendorp ◽  
...  
Keyword(s):  
Thin Film ◽  
Microelectromechanical Systems ◽  
Effect Of Water

scholarly journals Thin Film Encapsulation for RF MEMS in 5G and Modern Telecommunication Systems

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 2133 ◽  
Author(s):  
Anna Persano ◽  
Fabio Quaranta ◽  
Antonietta Taurino ◽  
Pietro Aleardo Siciliano ◽  
Jacopo Iannacci
Keyword(s):  
Thin Film ◽  
Microelectromechanical Systems ◽  
Rf Mems ◽  
Sacrificial Layer ◽  
Three Dimensional ◽  
Telecommunication Systems ◽  
Rf Performance ◽  
Three Dimensional Finite Element ◽  
The Impact ◽  
Thin Film Encapsulation

In this work, SiNx/a-Si/SiNx caps on conductive coplanar waveguides (CPWs) are proposed for thin film encapsulation of radio-frequency microelectromechanical systems (RF MEMS), in view of the application of these devices in fifth generation (5G) and modern telecommunication systems. Simplification and cost reduction of the fabrication process were obtained, using two etching processes in the same barrel chamber to create a matrix of holes through the capping layer and to remove the sacrificial layer under the cap. Encapsulating layers with etch holes of different size and density were fabricated to evaluate the removal of the sacrificial layer as a function of the percentage of the cap perforated area. Barrel etching process parameters also varied. Finally, a full three-dimensional finite element method-based simulation model was developed to predict the impact of fabricated thin film encapsulating caps on RF performance of CPWs.

The Fabrication of Thin Film NiTi Shape Memory Alloy Micro Actuator for MEMS Application

1999 ◽  
Author(s):  
John J. Gill ◽  
Ken Ho ◽  
Gregory P. Carman
Keyword(s):  
Thin Film ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Microelectromechanical Systems ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Vacuum System ◽  
Niti Shape Memory Alloy ◽  
Cylindrical Shape ◽  
Finish Temperature

Abstract Thin film SMA (Shape memory alloy) is a useful method for MEMS (Microelectromechanical Systems) actuator. This is because the thin film has an improved frequency response compared to bulk SMA, high work density, and produces large strain. A novel two-way thin film NiTi (Nickel Titanium) shape memory alloy actuator is presented in this paper. Thin film shape memory alloy is sputter-deposited onto a silicon wafer in an ultra high vacuum system. Transformation temperatures of the deposited NiTi film are measured by residual stress measurement at temperatures from 25 ° C to 120 ° C. Test results show that the Mf (Martensite Finish Temperature) is around 60 ° C and Af (Austenite Finish Temperature) is around 110 ° C. A free standing NiTi membrane (10 mm × 10mm and 3 μm thick) is fabricated using MEMS technology. We found that a mixture of HF (Hydro Fluidic Acid), HNO3 (Nitric Acid) and DI (Deionized) water with thick photo resist mask works best for the fabrication process. The membrane is hot-shaped in different shapes such as dome shape, pyramidal shape, and cylindrical shape. Results indicate that when the temperature of the NiTi film exceeds Af, the NiTi membrane transforms into the trained hot-shape. When the temperature cools down to room temperature, the membrane returns to the initial flat shape.

Thin Film NiTi Shape Memory Alloy Microactuator With Two-Way Effect

2000 ◽  
Author(s):  
John J. Gill ◽  
Gregory P. Carman
Keyword(s):  
Thin Film ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Frequency Response ◽  
Microelectromechanical Systems ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Vacuum System ◽  
Niti Shape Memory Alloy ◽  
Maximum Deflection

Abstract Thin film SMA (Shape memory alloy) is a useful material for MEMS (Microelectromechanical Systems) actuator. This is because the thin film has an improved frequency response compared to bulk SMA, high work density, and produces large strain. A novel two-way thin film NiTi (Nickel Titanium) shape memory alloy actuator is presented in this paper. Thin film shape memory alloy is sputter-deposited onto a silicon wafer in an ultra high vacuum system. Transformation temperatures of the NiTi film are determined by measuring the residual stress as a function of temperature. Test results show that the Martensite-Temperature-Finish (Mf) is approximately 60° C, and the Austenite-Temperature-Finish (Af) is 110° C. A free standing NiTi membrane (12 mm × 12 mm and 2.5 μm thick) is fabricated using MEMS technology. We found that a mixture of HF (Hydro Fluoric Acid), HNO3 (Nitric Acid) and DI (Deionized) water with thick photo resist mask works best for the fabrication process. The membrane is hot-shaped into a dome shape. Results indicate that when the temperature of the NiTi film exceeds Af, the NiTi membrane transforms into the trained hot-shape. When the temperature cools down to room temperature, the membrane returns to the initial flat shape. The performance of the SMA micro actuator is characterized with a laser measurement system for deflection vs. input power and frequency response. The maximum deflection of SMA microactuator is 230 μm. The corresponding frequency responses at the maximum deflection are 30 Hz with Copper (Cu) block placed underneath the microactuator and less than 1 Hz when Plexi-glass is placed.

Characteristics of Ti-Ni-Zr Thin Film Metallic Glasses / Thin Film Shape Memory Alloys for Micro Actuators with Three-Dimensional Structures

2015 ◽  
Vol 9 (6) ◽  
pp. 662-667 ◽  
Author(s):  
Junpei Sakurai ◽  
◽  
Seiichi Hata
Keyword(s):  
Thin Film ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Metallic Glasses ◽  
Microelectromechanical Systems ◽  
Three Dimensional ◽  
Eutectic Point ◽  
Supercooled Liquid ◽  
Supercooled Liquid Region ◽  
Liquid Region

In this paper, we investigate the characteristics of Ti-Ni-Zr thin film metallic glasses (TFMGs)/ shape memory alloys (SMAs) for microelectromechanical systems (MEMS) applications with three-dimensional structures. The amorphous Ti-Ni-Zr thin films having a Ni content of more than 50 at.% and Zr content of more than 11 at.% undergo glass transitions and are TFMGs. The Ti39Ni50Zr11TFMG has the lowest glass transition temperatureTgof 703 K and a wide supercooled liquid region ΔTof 57 K. Moreover, it has high thermal stability atTg. However, the apparent viscosity of the Ti39Ni50Zr11is higher than those of other Ti-Ni-Zr TFMGs. Moreover, the Ti-Ni-Zr TFMG exhibits higher viscosity than conventional TFMGs because the alloy composition of Ti-Ni-Zr TFMGs/SMAs is far from the eutectic point.

Nanoindentation Measurements on Low-k Porous Silica Thin Films Spin Coated on Silicon Substrates

2003 ◽  
Vol 125 (4) ◽  
pp. 361-367 ◽  
Author(s):  
Xiaoqin Huang ◽  
Assimina A. Pelegri
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Young’S Modulus ◽  
Microelectromechanical Systems ◽  
Young's Modulus ◽  
Porous Silica ◽  
Silicon Substrates ◽  
Silica Thin Films ◽  
Low K

MEMS (MicroElectroMechanical Systems) are composed of thin films and composite nanomaterials. Although the mechanical properties of their constituent materials play an important role in controlling their quality, reliability, and lifetime, they are often found to be different from their bulk counterparts. In this paper, low-k porous silica thin films spin coated on silicon substrates are studied. The roughness of spin-on coated porous silica films is analyzed with in-situ imaging and their mechanical properties are determined using nanoindentation. A Berkovich type nanoindenter, of a 142.3 deg total included angle, is used and continuous measurements of force and displacements are acquired. It is shown, that the measured results of hardness and Young’s modulus of these films depend on penetration depth. Furthermore, the film’s mechanical properties are influenced by the properties of the substrate, and the reproduction of the force versus displacement curves depends on the quality of the thin film. The hardness of the studied low-k spin coated silica thin film is measured as 0.35∼0.41 GPa and the Young’s modulus is determined as 2.74∼2.94 GPa.

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