scholarly journals Four-Probe Bridges for In-Line Determination of Thickness and Sidewall Etch Angle of Surface Micromachined Thin Films

2018 ◽  
Vol 8 (12) ◽  
pp. 2424 ◽  
Author(s):  
Haiyun Liu ◽  
Zhen Zhang ◽  
Jiaqi Chen
Keyword(s):  
Thin Films ◽  
Extraction Method ◽  
Microelectromechanical Systems ◽  
Low Cost ◽  
Fast Response ◽  
Thickness Measurement ◽  
Test Structure ◽  
Fabrication Process ◽  
Geometrical Parameters ◽  
Mems Fabrication

Geometrical parameters, such as the thickness and the sidewall etch angle of microelectromechanical systems (MEMS) thin films, are important information for device design and simulation, material property extraction, and quality control in a fabrication process line. This paper presents an in-line test microstructure for measuring geometrical parameters of surface micromachined thin films. The structure consists of four-probe bridges with continuous step structures and deposited at three different angles. The extraction method takes advantage of the resistances of the step structures to determine the thickness and the sidewall etch angle of the phosphosilicate glass (PSG) layer and the thickness of the polysilicon layer. The sheet resistance and the width of the test structure are required for the extraction method and can also be measured by using the test structure. Thicknesses of (2.080 ± 0.011) µm, (2.142 ± 0.012) µm, (1.614 ± 0.014) µm and (2.892 ± 0.012) µm are obtained for the Poly 1 layer, the Oxide 1 layer, the Poly 2 layer and the stacked layer of Oxide 1-Oxide 2, respectively. The sidewall etch angles for the Oxide 1 layer and the stacked layer of Oxide 1-Oxide 2 are obtained as (77.51 ± 0.61)° and (76.17 ± 0.91)°, respectively. In comparison to previously reported thickness measurement approaches, the proposed method is nondestructive, and makes use of four-point probe technique which is featured with electrical input and output configuration, simple operation, low cost, fast response, good repeatability and ease of integration. Therefore, this method is more suited to in-line monitoring the MEMS fabrication process.

Mechanical Properties of Ultrananocrystalline Diamond Thin Films for MEMS Applications

2002 ◽  
Vol 741 ◽  
Author(s):  
H.D. Espinosa ◽  
B. Peng ◽  
K.-H. Kim ◽  
B.C. Prorok ◽  
N. Moldovan ◽  
...  
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Elastic Moduli ◽  
Microelectromechanical Systems ◽  
Nanosized Particles ◽  
Good Reproducibility ◽  
Fracture Properties ◽  
Ultrananocrystalline Diamond ◽  
Mems Fabrication ◽  
Membrane Deflection

ABSTRACTMicrocantilever deflection and the membrane deflection experiment (MDE) were used to examine the elastic and fracture properties of ultrananocrystalline diamond (UNCD) thin films in relation to their application to microelectromechanical systems (MEMS). Freestanding microcantilevers and membranes were fabricated using standard MEMS fabrication techniques adapted to our UNCD film technology. Elastic moduli measured by both methods described above are in agreement, with the values being in the range 930 and 970 GPa with both techniques showing good reproducibility. The MDE test showed fracture strength to vary from 3.95 to 5.03 GPa when seeding was performed with ultrasonic agitation of nanosized particles.

scholarly journals Conductive-perovskite LaNiO3 thin films prepared by using solution process for electrode application

2018 ◽  
Vol 34 (2) ◽  
Author(s):  
TRINH BUI
Keyword(s):  
Thin Films ◽  
Low Cost ◽  
Solution Process ◽  
Fabrication Process ◽  
Cross Sectional ◽  
Structured Materials ◽  
Lanthanum Nickel Oxide ◽  
Dense Microstructure ◽  
Saturated Polarization ◽  
Ferroelectric Layer

Lanthanum nickel oxide LaNiO3 (LNO) is extensively known as one of typical perovskite-structured materials with metallic conductivity, which is suitable for the electrode application in electronic devices such as transistors or solar cells. Since LNO is a low-cost material and a simple fabrication process, it has been attracted much attention for commercialization. In this paper, we have focused on optimizing the fabrication process of LNO thin films on SiO2/Si substrate and Al foil by using a solution process. The crystal structure and surface morphology were characterized by using X-ray diffraction and field-emission scanning electron microscopy (FE-SEM), respectively. It was found that the LNO thin films annealed in range of 550-700oC for 30 min exhibited a well-formed crystallization and a dense microstructure. According to the SEM cross-sectional observation, the thickness of LNO thin films was estimated about 80 nm. Also, from the four-probe measurement method, the electrical resistivity of LNO thin film annealed at 600oC had a minimum value of 0.42 × 10-2 Ωcm, which was possibly comparable to conventional conductive oxides. As a result, the capacitor using Pb1.2(Zr0.4Ti0.6)O3 ferroelectric layer annealed at 600oC and LNO bottom electrode provided an interesting ferroelectricity, which included a remnant polarization of 21 µC/cm2 and a saturated polarization of 35 µC/cm2. Moreover, the leakage current density was lower than 2 × 10-5 A/cm2.

Complex permittivity measurements of RF plasma polymerized polyterpenol organic thin films employing split post dielectric resonator

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Kateryna Bazaka ◽  
Mohan V. Jacob
Keyword(s):  
Thin Films ◽  
Low Cost ◽  
Polymer Thin Films ◽  
Wavelength Region ◽  
Thickness Measurement ◽  
Organic Polymer ◽  
Rf Plasma ◽  
Potential Applications ◽  
Permittivity Measurements ◽  
Physical And Chemical

Abstract In the fields of organic electronics and biotechnology, applications for organic polymer thin films fabricated using low-temperature non-equilibrium plasma techniques are gaining significant attention because of the physical and chemical stability of thin films and the low cost of production. Polymer thin films were fabricated from non-synthetic terpinen-4-ol using radiofrequency polymerization (13.56 MHz) on low loss dielectric substrates and their permittivity properties were ascertained to determine potential applications for these organic films. Real and imaginary parts of permittivity as a function of frequency were measured using the variable angle spectroscopic ellipsometer. The real part of permittivity (k) was found to be between 2.34 and 2.65 in the wavelength region of 400–1100 nm, indicating a potential low-k material. These permittivity values were confirmed at microwave frequencies. Dielectric properties of polyterpenol films were measured by means of split post dielectric resonators (SPDRs) operating at frequencies of 10 GHz and 20 GHz. Permittivity increased for samples deposited at higher RF energy – from 2.65 (25 W) to 2.83 (75 W) measured by a 20-GHz SPDR and from 2.32 (25 W) to 2.53 (100 W) obtained using a 10-GHz SPDR. The error in permittivity measurement was predominantly attributed to the uncertainty in film thickness measurement.

Effective Conductivity Modelling of Polycrystalline ZnO Thin Films

1995 ◽  
Vol 403 ◽  
Author(s):  
M. Robles ◽  
J. Tagüeña-Martínez ◽  
J. A. Del Río
Keyword(s):  
Thin Films ◽  
Effective Conductivity ◽  
Structural Information ◽  
Low Cost ◽  
Mean Field ◽  
Field Approximation ◽  
Mean Field Approximation ◽  
Geometrical Parameters ◽  
Layer Adsorption ◽  
Conductivity Modelling

AbstractChemically deposited thin films have multiple applications, in particular for low cost solar cells production. However, due to their inhomogeneous structure, it is very difficult to predict their physical properties. In this work we present a mean field approximation to model the effective electrical conductivity of the polycrystalline ZnO chemical deposited thin films. Our model considers elliptical inclusions randomly distributed in a matrix. We compare with the experimental results of two different deposition methods: spray pyrolysis [1] and successive ion layer adsorption and reaction (SILAR) [2]. Supported by the structural information of these samples, we select the elliptical geometrical parameters. We obtain a good fit of the experimental measurements with our calculation.

scholarly journals Low-Cost Graphite on Paper Pressure Sensor for a Robot Gripper with a Trivial Fabrication Process

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3300 ◽  
Author(s):  
Jarred Fastier-Wooller ◽  
Toan Dinh ◽  
Van Dau ◽  
Hoang-Phuong Phan ◽  
Fuwen Yang ◽  
...  
Keyword(s):  
Pressure Sensor ◽  
Low Cost ◽  
Fast Response ◽  
Fabrication Process ◽  
Human Interface ◽  
Long Term Stability ◽  
Robot Gripper ◽  
Grasping Forces ◽  
Touch Devices ◽  
Flexible Pressure Sensor

A flexible pressure sensor with a rudimentary, ultra-low cost, and solvent-free fabrication process is presented in this paper. The sensor has a graphite-on-paper stacked paper structure, which deforms and restores its shape when pressure is applied and released, showing an exceptionally fast response and relaxation time of ≈0.4 ms with a sensitivity of −5%/Pa. Repeatability of the sensor over 1000 cycles indicates an excellent long-term stability. The sensor demonstrated fast and reliable human touch interface, and successfully integrated into a robot gripper to detect grasping forces, showing high promise for use in robotics, human interface, and touch devices.

Charge Trapping and Degradation Properties of PZT Thin Films for MEMS

1996 ◽  
Vol 444 ◽  
Author(s):  
Hyeon-Seag Kim ◽  
D. L. Polla ◽  
S. A. Campbell
Keyword(s):  
Thin Films ◽  
Loss Factor ◽  
High Field ◽  
Microelectromechanical Systems ◽  
Charge Trapping ◽  
Metal Organic ◽  
Electrical Reliability ◽  
Silicon Based ◽  
Degradation Properties ◽  
Organic Decomposition

AbstractThe electrical reliability properties of PZT (54/46) thin films have been measured for the purpose of integrating this material with silicon-based microelectromechanical systems. Ferroelectric thin films of PZT were prepared by metal organic decomposition. The charge trapping and degradation properties of these thin films were studied through device characteristics such as hysteresis loop, leakage current, fatigue, dielectric constant, capacitancevoltage, and loss factor measurements. Several unique experimental results have been found. Different degradation processes were verified through fatigue (bipolar stress), low and high charge injection (unipolar stress), and high field stressing (unipolar stress).

scholarly journals FEM Simulation of Frequency-Selective Surface Based on Thermoelectric Bi-Sb Thin Films for THz Detection

Photonics ◽  
2021 ◽  
Vol 8 (4) ◽  
pp. 119
Author(s):  
Anastasiia Tukmakova ◽  
Ivan Tkhorzhevskiy ◽  
Artyom Sedinin ◽  
Aleksei Asach ◽  
Anna Novotelnova ◽  
...  
Keyword(s):  
Thin Films ◽  
Response Times ◽  
Fem Simulation ◽  
Film Surface ◽  
Frequency Selective Surface ◽  
Fast Response ◽  
Radiation Absorption ◽  
Thz Radiation ◽  
Frequency Filter ◽  
Frequency Selective

Terahertz (THz) filters and detectors can find a wide application in such fields as: sensing, imaging, security systems, medicine, wireless connection, and detection of substances. Thermoelectric materials are promising basis for THz detectors’ development due to their sensitivity to the THz radiation, possibility to be heated under the THz radiation and produce voltage due to Seebeck effect. Thermoelectric thin films of Bi-Sb solid solutions are semimetals/semiconductors with the band gap comparable with THz energy and with high thermoelectric conversion efficiency at room temperature. Detecting film surface can be transformed into a periodic frequency selective surface (FSS) that can operate as a frequency filter and increases the absorption of THz radiation. We report for the first time about the simulation of THz detector based on thermoelectric Bi-Sb thin-filmed frequency-selective surface. We show that such structure can be both detector and frequency filter. Moreover, it was shown that FSS design increases not only a heating due to absorption but a temperature gradient in Bi-Sb film by two orders of magnitude in comparison with continuous films. Local temperature gradients can reach the values of the order of 100 K·mm−1. That opens new perspectives for thin-filmed thermoelectric detectors’ efficiency increase. Temperature difference formed due to THz radiation absorption can reach values on the order of 1 degree. Frequency-transient calculations show the power dependence of film temperature on time with characteristic saturation at times around several ms. That points to the perspective of reaching fast response times on such structures.

scholarly journals Clustering-Based Component Fraction Estimation in Solid–Liquid Two-Phase Flow in Dredging Engineering

Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5697
Author(s):  
Chang Sun ◽  
Shihong Yue ◽  
Qi Li ◽  
Huaxiang Wang
Keyword(s):  
Clustering Algorithm ◽  
Two Phase Flow ◽  
Low Cost ◽  
Fast Response ◽  
New Method ◽  
Phase Flow ◽  
Reference Distribution ◽  
Two Phase ◽  
Long Time ◽  
Solid Liquid

Component fraction (CF) is one of the most important parameters in multiple-phase flow. Due to the complexity of the solid–liquid two-phase flow, the CF estimation remains unsolved both in scientific research and industrial application for a long time. Electrical resistance tomography (ERT) is an advanced type of conductivity detection technique due to its low-cost, fast-response, non-invasive, and non-radiation characteristics. However, when the existing ERT method is used to measure the CF value in solid–liquid two-phase flow in dredging engineering, there are at least three problems: (1) the dependence of reference distribution whose CF value is zero; (2) the size of the detected objects may be too small to be found by ERT; and (3) there is no efficient way to estimate the effect of artifacts in ERT. In this paper, we proposed a method based on the clustering technique, where a fast-fuzzy clustering algorithm is used to partition the ERT image to three clusters that respond to liquid, solid phases, and their mixtures and artifacts, respectively. The clustering algorithm does not need any reference distribution in the CF estimation. In the case of small solid objects or artifacts, the CF value remains effectively computed by prior information. To validate the new method, a group of typical CF estimations in dredging engineering were implemented. Results show that the new method can effectively overcome the limitations of the existing method, and can provide a practical and more accurate way for CF estimation.

scholarly journals Direct measurement of the thermoelectric properties of electrochemically deposited Bi2Te3 thin films

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jose Recatala-Gomez ◽  
Pawan Kumar ◽  
Ady Suwardi ◽  
Anas Abutaha ◽  
Iris Nandhakumar ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermoelectric Properties ◽  
Bismuth Telluride ◽  
Indium Tin Oxide ◽  
Seed Layer ◽  
Room Temperature ◽  
Low Cost ◽  
Temperature Dependent ◽  
Temperature Heat ◽  
Electrochemically Deposited

Abstract The best known thermoelectric material for near room temperature heat-to-electricity conversion is bismuth telluride. Amongst the possible fabrication techniques, electrodeposition has attracted attention due to its simplicity and low cost. However, the measurement of the thermoelectric properties of electrodeposited films is challenging because of the conducting seed layer underneath the film. Here, we develop a method to directly measure the thermoelectric properties of electrodeposited bismuth telluride thin films, grown on indium tin oxide. Using this technique, the temperature dependent thermoelectric properties (Seebeck coefficient and electrical conductivity) of electrodeposited thin films have been measured down to 100 K. A parallel resistor model is employed to discern the signal of the film from the signal of the seed layer and the data are carefully analysed and contextualized with literature. Our analysis demonstrates that the thermoelectric properties of electrodeposited films can be accurately evaluated without inflicting any damage to the films.

Sign in / Sign up

Export Citation Format

Share Document