Abstract: A power diode device includes a substrate. The substrate includes a core layer of a first conductive type, a first diffusion layer of the first conductive type, a second diffusion layer of a second conductive type, and a heavily doped region of the second conductive type. The core layer is located between the first diffusion layer and the second diffusion layer. A thickness of the core layer is greater than that of the second diffusion layer. The heavily doped region is located in the second diffusion layer and extends toward the core layer to form a PN junction between the heavily doped region and the core layer. A method for manufacturing the power diode device is also provided.

Abstract: A contact tracking method and a related server are provided. In the method, the positioning information of multiple user equipments (UEs) is obtained. The UEs transmit wireless signals. The positioning information is determined based on the wireless signal. The wireless signal indicates a network provider identifier, a signal strength, or geolocation. The travel routes of the UEs are determined. Each travel route records the positioning information of one UE over time. The travel routes are analyzed to determine a contact situation between a first UE and a second UE of the UEs based on a contact criteria.

Abstract: A contact tracking method and a related server are provided. In the method, the positioning information of multiple user equipments (UEs) is obtained. The UEs transmit wireless signals. The positioning information is determined based on the wireless signal. The wireless signal indicates a network provider identifier, a signal strength, or geolocation. The travel routes of the UEs are determined. Each travel route records the positioning information of one UE over time. The travel routes are analyzed to determine a contact situation between a first UE and a second UE of the UEs based on a contact criteria.