Enhancement-Mode 300-mm GaN-on-Si(111) With Integrated Si CMOS for Future mm-Wave RF Applications

A 300-mm GaN-on-Si(111) high- k gate dielectric E-mode GaN MOSHEMT technology is demonstrated with uniform process and wafer characteristics. The E-mode GaN MOSHEMT of L_{\mathrm{G}} = 90 nm, L_{\mathrm{GS}} = L_{\mathrm{GD}} = 80 nm, is enabled by 300-mm process capabilities in deep U (DUV) lithography, MOCVD, atomic layer etch (ALE), atomic layer deposition (ALD), and Cu interconnect. The GaN MOSHEMT shows excellent on/off characteristics, low leakages, low R_{\mathrm{on}} , high I_{\mathrm{D}} , and f_{T} / f_{\mathrm{MAX}} of 140/280 GHz. A 42-GHz mm-Wave power amplifier (PA) fabricated in this process for the first time demonstrates a saturated power of 25.6 dBm, a linear gain of 22.5 dB, and a PAE of 35.7%. In this technology, high f_{T} / f_{\mathrm{MAX}} is obtained by scaling to thin equivalent oxide thickness (EOT) and short L_{\mathrm{G}} , and high breakdown is achieved with extended L_{\mathrm{GD}} and field plating. Si CMOS can be integrated with this GaN technology using 3-D layer transfer and does not alter the RF performance of the GaN MOSHEMT. Record f_{\mathrm{MAX}} = 700 GHz ( f_{T} =