High performance micromachined GaN on Si HEMT with backside diamondlke-carbon/titanium heat dissipation layer

In this work, a thermally stable air-bridged matrix (ABM) AlGaN/GaN high electron mobility transistor (HEMT) with micromachined diamondlke carbon (DLC)/Titanium thermal-distributed layers was demonstrated. After removing the Si substrate beneath the HEMT, the DLC/Ti heat dissipation layers were deposited on the backside of the HEMT, and a significant breakdown voltage improvement was observed. The drain and source terminals were arranged as the matrix type. Compared to the traditional multi-fingers HEMT, the current density was doubled. In addition, the self-heating phenomenon of power cell was also suppressed by the backside DLC/Ti heat dissipation layer.