摘要:
A novel surface acoustic wave device with a decreased velocity dispersion and a low insertion loss as well as the fabrication method therefor is provided. The surface acoustic wave device includes a substrate, an insulating layer with an indentation on the substrate, a silicon layer with a first portion on the insulating layer and a second portion suspended above the indentation, a piezoelectric layer on the first and the second portions of the silicon layer, and at least an electrode on the piezoelectric layer.
摘要:
A novel surface acoustic wave device with a decreased velocity dispersion and a low insertion loss as well as the fabrication method therefor is provided. The surface acoustic wave device includes a substrate, an insulating layer with an indentation on the substrate, a silicon layer with a first portion on the insulating layer and a second portion suspended above the indentation, a piezoelectric layer on the first and the second portions of the silicon layer, and at least an electrode on the piezoelectric layer.
摘要:
A novel surface acoustic wave device with a decreased velocity dispersion and a low insertion loss as well as the fabrication method therefore is provided. The surface acoustic wave device includes a substrate, an insulating layer with an indentation on the substrate, a silicon layer divided by an etched window with a first portion on the insulating layer and a second portion suspended above the indentation, a piezoelectric layer on the first and the second portions of the silicon layer, and at least an electrode on the piezoelectric layer.
摘要:
A novel surface acoustic wave device with a decreased velocity dispersion and a low insertion loss as well as the fabrication method therefor is provided. The surface acoustic wave device includes a substrate, an insulating layer with an indentation on the substrate, a silicon layer with a first portion on the insulating layer and a second portion suspended above the indentation, a piezoelectric layer on the first and the second portions of the silicon layer, and at least an electrode on the piezoelectric layer.
摘要:
A thin film layered surface acoustic wave device includes a substrate, a GaN piezoelectric film, an AlN piezoelectric film and interdigital transducer electrodes. The GaN piezoelectric film is deposited on the substrate by chemical vapor deposition (CVD) or physical vapor deposition (PVD) method. Then the AlN piezoelectric film is deposited on top surface of the GaN piezoelectric film by the same way. Finally, the interdigital transducer electrodes are deposited on top surface of AlN piezoelectric film and form by etching of lift off method. Accordingly, high operating frequency and low loss surface acoustic wave devices can be produced which can be integrated with high frequency devices, such as HBT and HEMT, and different devices.
摘要:
The present invention provides a light-enhancing component and a fabrication method thereof by using the focused-ion-beam. In the present invention, the surface plasmon polariton structure is coated on the surface of the optical fiber so as to form the light-enhancing component. When the light passes through the optical fiber, the luminous flux transmitted through the aperture on the surface plasmon polariton is enhanced, and the light beam smaller than the diffraction limitation can be transmitted to the far-field, i.e. the nano-optic sword is formed. The light-enhancing component of the present invention can be used for the optical data storage, the optical microscopy, the biomedical detections and the lithography to perform the extra optical resolutions beyond the diffraction limitation.
摘要:
An internal combustion engine is selectably operable in one of homogeneous charge compression ignition (HCCI) mode with low lift intake and exhaust valve profiles and spark ignition (SI) mode with high lift intake and exhaust valve profiles. Transition from a current combustion mode to a desired combustion mode includes phase adjusting the one of the intake and exhaust valves exhibiting a greater effect upon an effective cylinder volume for a given phase adjustment in the desired combustion mode based upon a desired phasing for the desired combustion mode prior to lift adjusting the one of the intake and exhaust valves and adjusting the other of the intake and exhaust valves.
摘要:
The disclosure sets forth operating a spark-ignition, direct-fuel injection internal combustion engine, including transitioning the engine from operating in a stratified charge combustion mode to operating in a homogeneous charge combustion mode. External EGR flow is discontinued, and an in-cylinder trapped air mass and an in-cylinder EGR mass in an air intake system of the engine are estimated. Engine throttle position is controlled to achieve trajectories for air/fuel ratio and the in-cylinder EGR mass determined based upon the estimated in-cylinder trapped air mass and the in-cylinder EGR mass in the air intake system. A double-injection fueling strategy and a single-injection fueling are used during the transition.
摘要:
A method to control operation of an engine during a transition from a first to a second combustion mode is provided. The engine includes a controllable throttle valve, a variable valve actuation system for controlling openings and closings of intake and exhaust valves, and, an intake and an exhaust. Mass airflow, intake manifold pressure, and cylinder volume to operate the engine in the second combustion mode and meet an operator torque request are determined. Current states for mass airflow, intake manifold pressure, and cylinder volume are determined. An opening position of the controllable throttle valve and the openings and the closings of the intake and exhaust valves are controlled during the transition to the second combustion mode based upon differences between the current states for mass airflow, intake manifold pressure, and cylinder volume, and, the mass airflow, the intake manifold pressure, and the cylinder volume.
摘要:
A method for selecting a preferred combustion mode for an internal combustion engine operative in a plurality of combustion modes is described. The method includes selecting a combustion mode in terms of first and second engine parameters, and separating the engine operating region into zones defined by the first parameter. Each of the zones is further separated into sub-zones defined by the second parameter. A combustion mode is associated with each of the sub-zones. Operating states are determined for the first and second parameters. One of the zones is identified based upon the state for the first parameter. One of the sub-zones of the identified zone is identified based upon the state for the second parameter, along with a combustion mode associated with the identified sub-zone. The engine is controlled to the preferred combustion mode, depending upon hysteresis.