First Demonstration of Monolithic Self-aligned Heterogeneous Nanosheet Channel Complementary FETs with Matched VT by Band Alignments of Individual Channels

Monolithic 3D stacked Ge
0.9
Sn
0.1
nanosheet and Ge
0.75
Si
0.25
nanosheet complementary FETs with multiple P/N junction isolation by in-situ doped CVD epitaxy are experimentally demonstrated. Heterogeneous channels with common single work function metal gate structure are fabricated as a CMOS inverter with the matched V
T
and good voltage transfer characteristics. V
T
tuning is achieved individually by the band alignment of GeSi and GeSn for n-channel and p-channel, respectively, for the first time. The Hf
0.2
Zr
0.8
O
2
gate stacks with extremely high κ of 47 are integrated to enhance the I
ON
of CFET for high performance. The monolithic stacked heterogeneous complementary FETs without the need of wafer bonding, dielectric isolation, selective epitaxial growth, and dual work function metal can simplify the process for transistor 3D stacking.