Relaxed Ge0.97Sn0.03 P-channel tunneling FETs with high drive current fabricated on Si and further improvement enabled by uniaxial tensile strain

We fabricated relaxed Ge_0.97Sn_0.03 pTFETs on Si(001). The devices show much higher I_ON than SiGe, Ge, and compressively strained GeSn planer pTFETs in literatures. For the first time, I_ON enhancement in GeSn pTFET utilizing uniaxial strain is reported. By applying 0.14% uniaxial tensile strain along channel direction, Ge_0.97Sn_0.03 [110] pTFETs achieve ~ 10% I_ON improvement, over relaxed devices at |V_GS - V_TH| = |V_DS| = 1.0 V. Calculation demonstrates that the reduction of direct E_G by tensile strain results in an enhanced G_BTBT in GeSn, leading to improvement of I_ON in uniaxially tensile strained pTFET.