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

Abstract

A 300-mm GaN-on-Si(111) high- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> gate dielectric E-mode GaN MOSHEMT technology is demonstrated with uniform process and wafer characteristics. The E-mode GaN MOSHEMT of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$L_{\mathrm {G}}$ </tex-math></inline-formula> = 90 nm, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$L_{\mathrm {GS}}$ </tex-math></inline-formula> = <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$L_{\mathrm {GD}}$ </tex-math></inline-formula> = 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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$R_{\mathrm {on}}$ </tex-math></inline-formula> , high <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I_{\mathrm {D}}$ </tex-math></inline-formula> , and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{T}/f_{\mathrm {MAX}}$ </tex-math></inline-formula> 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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{T}/f_{\mathrm {MAX}}$ </tex-math></inline-formula> is obtained by scaling to thin equivalent oxide thickness (EOT) and short <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$L_{\mathrm {G}}$ </tex-math></inline-formula> , and high breakdown is achieved with extended <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$L_{\mathrm {GD}}$ </tex-math></inline-formula> 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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{\mathrm {MAX}}$ </tex-math></inline-formula> = 700 GHz ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{T}$ </tex-math></inline-formula> = 115 GHz) is obtained with an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$L_{\mathrm {G}}$ </tex-math></inline-formula> = 50 nm GaN MOSHEMT with submicrometer source field plate (FP) fabricated using this 300-mm GaN MOSHEMT process with integrated Si CMOS. Finally, progress on process design kit (PDK) development for this technology is reported.