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With the rapid development of vehicle information systems, liquid crystal displays (LCDs) have been widely used to enhance information experience. A linear vibration motor is usually placed behind the LCD to provide sufficient haptic feedback. A linear vibration motor with a large permanent magnet causes massive flux leakage around the display. As a result, it may cause unpredictable harm to people with implanted medical devices. Therefore, in this paper, a novel magnetic circuit design of a slim-width type linear vibration motor is introduced to reduce the static magnetic flux leakage. The haptic performance of the slim-width type linear vibration motor was analyzed using the electromagnetic-mechanical coupling method. Three types of experimental results were obtained to verify the analysis results. In conclusion, compared to the prototype motor, the slim-width type linear vibration motor proposed in this paper exhibits significant flux leakage reduction of 94.01% and 96.34% at the measuring positions. Furthermore, the slim-width type linear vibration motor exhibits an acceleration similar to that of the prototype motor.

Recently, miniaturization has become a hot topic in microspeaker research and has attracted considerable attention. However, the acoustic quality of microspeakers-evaluated in terms of the sound pressure level (SPL)–declines if their dimensions are reduced. This study discusses the application of zeolite in the microspeaker box without causing a change in speaker dimensions. The equivalent circuit method and Langmuir adsorption isotherm have been used to analyze SPL of the microspeaker box. Based on the analysis results obtained in this study, microspeaker samples have been manufactured and their effectiveness has been experimentally verified. Simulation and experimental results reveal that the zeolite can improve SPL by approximately 3.5 dB over a frequency range of 100–1000 Hz.

The spring structure design and magnetic circuit optimization were considered to design a novel linear vibration motor with advantages of lower cost and similar motor performance compared to a coin-type vibration motor. A vibration motor is inserted in an electronic cigarette to provide haptic feedback to remind the user that the electronic cigarette is ready to operate. For the new generation of electronic cigarettes, new vibration motors require smaller size, lower cost, and acceptable motor performance. A three-dimensional finite element method has been used to find the coil&rsquo, s magnetic flux density and von Mises stress distribution in the spring. Moreover, the electromagnetic-mechanical coupling method has been employed to find the motor acceleration on a dummy jig. The acceleration of the vibration motor was obtained to verify the analysis results by experiment. The experiment results verified the analysis results of the linear vibration motor. Compared to a coin-type vibration motor, the novel linear vibration motor has 9.09% and 80.77% reductions in total thickness and manufacturing cost, and a 40.0% improvement in acceleration.

Micro speakers are playing an increasingly important role with the development of multimedia devices. This study applies the lumped-parameter method, which uses an equivalent circuit to model the electromagnetic and mechanical domains. The acoustic domain is modeled using the finite element method. Based on the analysis tool, the use of a screen is analyzed, and the screen is designed to depress the acoustic resonance in the sound-pressure-level curve and improve the performance. The samples are fabricated, and the experiment verifies the analysis method. The experimental result shows that the peak and dip due to the standing wave are cancelled, and the frequency response is smooth when the screen is used.

Currently, balanced armature (BA) receivers are frequently used in earphones, owing to their small size and superior sound quality. However, the reliability of BA receiver earphones has become a considerable challenge, as they easily fail when subjected to external forces, especially during drop impacts. In addition, the original gasket cannot protect the BA receiver well. Therefore, this article focuses on improving the reliability of BA receiver earphones by designing a novel concept for the gasket. Based on a simplified model and analysis methods, the maximum von Mises stress on the armature with different drop directions and the maximum von Mises stress point must first be determined. The gasket was divided into two parts, one for linking and the other for shock absorption. This article focused on the design of the shock absorption structure. A novel concept gasket was proposed, and the analysis results showed that the gasket improved the shock absorption performance. For demonstrating the validity of the shock absorption performance of the novel concept gasket, three confirmatory experiments were performed: the drop impact test, X-ray photography, and sound performance, which included the sound pressure level and total harmonic distortion. The analysis results were experimentally verified.

With the development of multimedia devices, earphones are playing an increasingly important role. This article applies the lumped parameter method using an equivalent circuit to model the electromagnetic, mechanical, and acoustic domains of earphones. Then, parameters are determined according to the dimensions and material properties of earphone parts. On the basis of the analysis tool and determined parameters, a Helmholtz protector is analyzed and designed to improve the high-frequency response. Samples are fabricated, and the experiment verifies the analysis method. The experimental result shows that the peaks at 7 k and 10 k are decreased at 8.05 dB and 7.89 dB. The root means square value of SPL deviation compared with target curve decreased from 9.77 to 4.39. High-frequency response is improved by using the Helmholtz protector.

The balanced armature receiver (BAR) is a product based on multiphysics that enables coupling between the electromagnetic, mechanical, and acoustic domains. The three domains were modeled using the lumped parameter method (LPM) that takes advantage of an equivalent circuit. In addition, the combined finite element method (FEM) and boundary element method (BEM) was also applied to analyze the BAR. Both simulation results were verified against experimental results. The proposed LPM can predict the sound pressure level (SPL) by making use of the BAR parts dimension and material property. In addition, the previous analysis method, FEM/BEM, took 36 h, while the proposed LPM takes 1 h. So the proposed LPM can be used to check the BAR parts&rsquo, dimension and material property influence on the SPL and develop the BAR product efficiently.

In the era of multimedia devices, smartphones have become the primary device for consuming multimedia content. As technological developments have facilitated a more immersive multimedia experience, enlarged displays and the use of several sensors have limited the allowable size of microspeakers. Although sound plays an important role when consuming multimedia content, the limited space for microspeakers in modern devices leads to poor acoustic performance, especially at low frequencies. To address this issue, this paper proposes a novel microspeaker structure that enhances the low-frequency sound pressure level (SPL), while also featuring reduced exterior dimensions. The structure was designed and analyzed using 3D finite element analysis. Through coupling analysis, the simulation results were verified on the basis of the experimental results. The novel microspeaker has one outer magnet surrounding the entire coil, unlike in prototype microspeakers, which have two outer magnets. The gap between the top plates and coil is reduced, and a new type of coil is introduced for the purpose of increasing electromagnetic force. The samples were manufactured, and their SPLs were tested in an anechoic chamber. The experimental results prove that the proposed microspeaker offers an improved SPL at low frequencies compared with prototype microspeakers.

With the development of technology, multimedia devices such as smartphones, tablets, and wearable devices have become necessities in our lives, and many new products are introduced every year. Companies are expanding smartphone displays and are developing bezel-less display panel designs. The enlarged display limits the space available for a speaker, and a new actuator must therefore be developed. Indirect-vibration actuators were developed for full-wide display designs. Using the same sound-generation principle as that of the indirect-vibration actuator, the mechanism and design of the direct-vibrating actuator is proposed in this paper. Using 3D finite element method (FEM), the force factor is obtained and used for design optimization. A sample is produced, and an experiment is conducted for sound pressure level (SPL) comparison. The experiment results show that the newly designed direct-vibration actuator can replace the dynamic receiver in mobile devices and enable the application of the bezel-less display design.

Linear vibration motors are becoming more popular for use in haptic applications owing to their better performance. However, a permanent magnet with a large volume causes massive magnetic flux leakage, which can be harmful to passengers with a cardiac pacemaker or an implantable-cardioverter defibrillator. The magnetic flux leakage is calculated using the 3D finite element method, which can also be applied to obtain the force factor. Then, the displacement and impedance are obtained to check the performance of the linear vibration motor by utilizing the finite element method. A prototype of a linear vibration motor is analyzed and verified based on the experimental results. Based on the analysis methods, three new designs are proposed to reduce the magnetic flux leakage to within 50 G. The final design shows a 93.07% reduction of the magnetic flux leakage while maintaining the same performance as the prototype. To verify the validity of the analysis results, three experimental results were obtained: the magnetic flux leakage, displacement, and impedance. The experimental results are in good agreement with the analysis results.

The surface transient in Si and SiGe for secondary ion mass spectrometry (SIMS) analysis with low-energy and obliquely incident O 2 + beams was studied. In particular, the transition width (z tr , the depth at which equilibrium secondary Si + intensity was reached) was measured for various impact energies (0.56 keV ≤ E p ≤ 2 keV) and incidence angle (45° 60°, the transition widths for relatively fresh surfaces were 3-4 nm, offering good conditions for ultra-shallow SIMS analysis. At E p = 1 keV and 0 = 60°, the differences in z tr between various secondary ions (Si + , SiO + , Ge + and GeO + ) were marginal and only O + and Si 2 + ions reached equilibrium significantly earlier. We found that z tr is about twice the mean penetration depth of the primary ions. In addition, the thickness of the native oxide of Si wafers was measured as a function of the storage time in air. It varied from 0.6 nm after 1 day to 1.5 nm after 2 years.

A novel approach for the determination of the incidence angle in a magnetic-sector SIMS instrument is described. It is based on accurate mapping of the primary beam in the extraction field near the sample surface. The accuracy of the method and the applicability of simple formulas are discussed in detail. In addition, the variation in the incidence angle over the rastered area has been measured and it is shown that, by adjusting the potential on the extraction electrode, this angle can be selected. Grazingly incident primary beams with energies well below 1 keV have been produced.

By the use of a deceleration electrode in the primary beam line of a magnetic sector SIMS instrument, an O 2 + primary beam of variable energy and angle has been produced. The SIMS measurements of ultrathin Ge and B layers in Si were performed with low-energy (0.7-2 keV) and grazingly incident (50-75°) O 2 + ions. Consequently, ultrahigh depth resolution with characteristic exponential leading and decay lengths of 0.25 and 0.9 nm, respectively, and 1.6 nm full width at half-maximum for a Ge delta layer was obtained. A depth profile analysis without any appreciable loss in depth resolution was achieved down to a depth of 1 μm with a 1 keV 60° O 2 + beam. Furthermore, good dynamic range, acceptable detection limit and moderate sputtering rates were achieved in this ultrahigh depth resolution mode.

As traditional poly-silicon gated MOSFET devices scale, the additional series capacitance due to poly-silicon depletion becomes an increasingly large fraction of the total gate capacitance, excessive boron penetration causes threshold voltage shifts, and the gate resistance is elevated. To solve these problems and continue aggressive device scaling we are studying metal electrodes with suitable work-functions and sufficient physical and electrical stability. Our studies of metal gates on HfO2 indicate that excessive inter-diffusion, inadequate phase stability, and interfacial reactions are mechanisms of failure at source drain activation temperatures that must be considered during the electrode selection process. Understanding the physical properties of the metal gate – HfO2 interface is critical to understanding the electrical behavior of MOS devices. Of particular interest is Fermi level pinning, a phenomenon that occurs at metal – dielectric interfaces which causes undesirable shifts in the effective metal work function. The magnitude of Fermi level pinning on HfO2 electrodes is studied with Pt and LaB6 electrodes. In addition, the intrinsic and extrinsic contributions to Fermi level pinning of platinum electrodes on HfO2 gate dielectrics are investigated by examining the impact of oxygen and forming gas anneals on the work function of platinum-HfO2-silicon capacitors. The presence of interfacial oxygen vacancies or Pt-Hf bonds is believed to be responsible for a degree of pinning that is stronger than predicted from the MIGS model alone. Interface chemistry and defects influence the effective metal work function.

A jet model for the jet power arising from a steady, optically thin, advection dominated accretion flow (ADAF) around a Kerr black hole (BH) is proposed. We investigate the typical numerical solutions of ADAF, and calculate the jet power from an ADAF using a general relativistic version of electronic circuit theory. It is shown that the jet power concentrates in the inner region of the accretion flow, and the higher the degree to which the flow advection-dominated is, the lower the jet power from the ADAF is.

Electroless plated CoWB and CoWPB films were studied for copper cap applications in semiconductor device processing. Both films were found to be polycrystalline but introduction of phosphorus made the CoWPB film less crystalline than CoWB. Films were stable for four cycles of thermal annealing with each cycle consisting of a 2 hour anneal at 400åC. Cu diffused through thin cap films after one thermal cycle but for subsequent cycles no significant increase in copper concentration was observed. It appeared that the solubility limit of Cu in cobalt is reached limiting further diffusion of Cu after the first cycle at this annealing temperature. Electrical data collected for 3.9m snake and comb test structures with CoWB and CoWPB showed less than one order of magnitude increase in leakage and less than a 1.5 % change in resistance.