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: A cell mechanical stimulating device for applying to at least one cell sample is provided. The device includes a base unit, at least one moving component and at least one magnetic component. The base unit includes a base body and a separating lid. The base body includes at least one culturing chamber and a bottom chamber surface. The cell sample is disposed in the culturing chamber, and the separating lid encloses the culturing chamber. The magnetic component drives the moving component to shift between a pressurizing position and a non-pressurizing position. At the pressurizing position, the moving component moves toward the bottom chamber surface and pressurizes the cell sample. At the non-pressurizing position, the moving component moves toward the separating lid and the pressure on the cell sample is removed. The cell sample is pressurized by the magnetic component driving the moving component.