$W_{e}=100\mathrm{nm}$ InP/lnGaAs DHBT with Self-aligned MOCVD Regrown p-GaAs Extrinsic Base Exhibiting $1\Omega-\mu\mathrm{m}^{2}$ Base Contact Resistivity

We report DC results from a $W_{e}=100\mathrm{nm\ InP}/\mathrm{InGaAs}$ DHBT technology with a self-aligned MOCVD regrown GaAs extrinsic base providing low base access resistance $R_{bb}$ while maintaining acceptable DC current gain $\beta$ . A $0.09\times 5\mu \mathrm{m}^{2}$ transistor exhibits a base contact resistivity $\rho_{c}=1\Omega-\mu \mathrm{m}^{2}$ , and a peak $\beta\sim 15$ . The HBTs exhibit a common-emitter breakdown voltage $BV_{CEO}=3.6\mathrm{V}(J_{C}=10\mu \mathrm{A}/\mu \mathrm{m}^{2})$ . According to the general scaling law for InP HBTs in [1], the low $\rho_{c}$ meets the requirement for $f_{max}=2.8\mathrm{THz}$ operation.