Wafer-Level-Packaged $X$-Band Internally Matched Power Amplifier Using Silicon Interposer Technology

In this letter, we propose a wafer-level-packaged (WLP) $X$ -band internally matched power amplifier (IMPA) using silicon interposer technology. The proposed WLP IMPA consists of a fully embedded commercial GaN HEMT transistor (TR) embedded in the silicon wafer and matching networks. The proposed IMPA enhanced the output power and efficiency compared with the conventional quasi-monolithic microwave integrated circuit (MMIC) high power amplifiers (HPAs) due to removal of bonding wires between matching networks and TR. Further, it provided a high level of integration and reduces the manufacturing cost associated with the silicon interposer technique. For experimental validation, the proposed WLP IMPA was designed and fabricated at 10.2 GHz for military radar application. The results show that the output power and drain efficiency at saturation point were 48.54 dBm (71.45 W) and 50.29%, respectively, based on the pulse signal test (100- $\mu \text{s}$ pulsewidth and 10% duty). The dimensions of the fabricated WLP IMPA were 7.5 mm $\times5.8$ mm $\times0.12$ mm.