Fabrication process and advantages of the new generation quasi-monolithic integration technology are presented. The novel fabrication process gives excellent advantages such as extremely low thermal resistance, and a much lower thermal stress than the earlier QMIT concept [1]. This highly improves the packaging lifetime and electrical characteristics of the active devices. The fabrication process is simple and compatible with fabrication of high-Q passive elements. In comparison to the old concept of QMIT, elimination of air-bridges in this technology not only reduces the parasitics but also enables the fabrication of the rest of the circuit after measuring the microwave characteristics of the embedded active devices. This makes very accurate microwave and millimetrewave designs possible. Using the new fabrication process, microwave and millimetrewave circuits (with both coplanar and microstrip lines) containing power devices have for the first time been realised.

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