In this article, we report a compact and low‐profile GaN‐based broadband power amplifier using silicon interposer‐MMIC (iMMIC) technology. The iMMIC technology enables a GaN HEMT to be embedded in the silicon substrate, and passive circuit elements such as metal‐insulator‐metal (MIM) capacitors, spiral inductors, and thin film resistors to be implemented on the high‐resistivity silicon (HRS) substrate using standard integrated passive device (IPD) process, so that the final power amplifier is almost indistinguishable from a single GaN MMIC power amplifier. The RLC matched all‐pass network and LC ladder type low‐pass network are employed as the input matching network and output matching network, respectively. The proposed power amplifier has a Psat of 39.1 to 39.2 dBm with a power‐added efficiency (PAE) of 40% to 50.5% in the frequency range of 2.1 to 3.5 GHz under continuous wave (CW) input signal. The proposed iMMIC power amplifier occupies only 9.9 mm2.

In this study, we propose an algorithm that complements the frequency dependence of the relative permittivity conversion equation applied for the measurement of relative permittivity through a ring resonator. The broadband electrical characteristics of an epoxy molding compound (EMC) used in the fan-out wafer-level packaging (FOWLP) process were measured using our algorithm. By proposing a formula for calculating the permittivity that reflects the current distribution at the multiplied frequency of the microstrip ring resonator, the effective range of the permittivity of the sample was extended to the multiplied frequency region. Thus, a more sophisticated and effective complex permittivity was calculated over a wide band. The relative permittivity of the EMC measured by the proposed technique was 3.836 and the dielectric loss tangent was 0.022. This technique improved the relative permittivity measurement error rate by 3.95 % and the measurement error rate of the dielectric loss tangent by 8.4 %p compared to the conventional method.