Abstract: A semiconductor structure is provided. The semiconductor structure includes a substrate, a channel layer, a barrier layer, a compound semiconductor layer, a gate electrode, and a stack of dielectric layers. The channel layer is disposed on the substrate. The barrier layer is disposed on the channel layer. The compound semiconductor layer is disposed on the barrier layer. The gate electrode is disposed on the compound semiconductor layer. The stack of dielectric layers is disposed on the gate electrode. The stack of dielectric layers includes layers having different etching rates.

Abstract: The ink cartridge is provided with a pressure controller to regulate the inner pressure therein by atmospheric pressure while the ink stored in the ink cartridge is gradually drained off. The ink is stored in a container with negative pressure therein, and at least one through hole formed on the container is used to connect to the atmosphere, and at least one recess is formed on the inner wall of the through hole. The pressure controller has a plug movably disposed on the through hole and the recesses. The recesses are used as a channel to allow the entrance of the atmospheric air, and the plug can be automatically moved so as to enlarge the clearance between the plug and the through hole while the ink stored in the ink cartridge is gradually drained off. The inputted air can effectively reduce the negative pressure in the container, and therefore the printing process of the ink cartridge can be proceeding steadily.

Abstract: An automatic alignment system is used to correct the offset error of a bidirectional printing device. The positional offset between the forward printing and the backward printing is compensated by adjusting the position of the printing cartridge. The actual position of the cartridge is sensed by a light detector, which is shuttered when the moving cartridge, driven by a microstepping motor, passes through the sensor. Based on the difference between the actual position and the correct theoretical position, the cartridge position is automatically adjusted to correct the offset error. For fine adjustment, time delay can be used in addition to the positional adjustment of the cartridge.

Abstract: The ink cartridge is provided with a pressure controller to regulate the inner pressure therein by atmospheric pressure while the ink stored in the ink cartridge is gradually drained off. The ink is stored in a container with negative pressure therein, and at least one through hole formed on the container is used to connect to the atmosphere, and at least one recess is formed on the inner wall of the through hole. The pressure controller has a plug movably disposed on the through hole and the recesses. The recesses are used as a channel to allow the entrance of the atmospheric air, and the plug can be automatically moved so as to enlarge the clearance between the plug and the through hole while the ink stored in the ink cartridge is gradually drained off. The inputted air can effectively reduce the negative pressure in the container, and therefore the printing process of the ink cartridge can be proceeding steadily.

Abstract: The present invention provides a pressure control apparatus for an ink-jet pen. The apparatus will adjust the back pressure of ink in the reservoir of the ink-jet pen in a suitable range when the ink is used gradually. The apparatus includes a pressure adjusting element and a hole furnished on the bottom wall of a reservoir. Under normal condition, the pressure adjusting element contacts tightly to the hole and prevents air from ingression. When the back pressure increases gradually to an extent, the ambient air will overcome the pressure of a spring which provides force to the pressure adjusting element, thus move the pressure adjusting element to leave a clearance to the hole and let some air bubbles ingressing into the reservoir till the back pressure decreases to a certain value. After the back pressure returns to the certain value, the pressure adjusting element further contacts the hole and prevents air from ingression, thus maintains a suitable back pressure of the ink in the reservoir.