Abstract: A packaging structure includes: a substrate provided with a through-cavity penetrating up and down, and a metal heat sink on a front surface of the substrate; a bonding chip mounting area and a first passive element mounting area on the front surface, and a flip chip mounting area, a second passive element mounting area and a pin lead mounting area are provided on a back surface of the substrate; a first sealing ring located at the periphery of the bonding chip mounting area and the first passive element mounting area; a first cover plate packaged on the first sealing ring; a second sealing ring located at the periphery of the flip chip mounting area and the second passive element mounting area with the pin lead mounting area being located at the periphery of the second sealing ring; and a second cover plate packaged on the second sealing ring.

Abstract: An online monitoring device for fouling and slagging based on capacitance principle differential measurement includes multiple measuring devices arranged at the same height of the boiler heating surface. Each measuring device includes a fixed sleeve and a sensor, one end of the fixed sleeve is fixed on the boiler heating surface, the sensor is connected with the fixed sleeve through screw threads, the end of the sensor near the boiler is equipped with a measuring probe. When measuring the thickness of ash residue on the monitoring surface, three sets of the measuring devices are at the same height of the monitoring surface. Each sensor is adjusted at a different position in the corresponding fixed sleeve to realize the differential measuring on ash residue thickness. Thus, the thickness of ash residue on the monitoring surface can be calculated based on the measured capacitance by applying the capacitance formula of planar capacitor.

Abstract: A packaging structure includes: a substrate provided with a through-cavity penetrating up and down, and a metal heat sink on a front surface of the substrate; a bonding chip mounting area and a first passive element mounting area on the front surface, and a flip chip mounting area, a second passive element mounting area and a pin lead mounting area are provided on a back surface of the substrate; a first sealing ring located at the periphery of the bonding chip mounting area and the first passive element mounting area; a first cover plate packaged on the first sealing ring; a second sealing ring located at the periphery of the flip chip mounting area and the second passive element mounting area with the pin lead mounting area being located at the periphery of the second sealing ring; and a second cover plate packaged on the second sealing ring.