Dual-MOSFET structure for suppression of kink in SOI MOSFETs at room and liquid helium temperatures

The dual-MOSFET structure proposed consists of two SOI nMOSFETs, T ₁ and T₂, in series, but measured as a single device (T₁ to the source and T₂ to the drain) with a common gate electrode. The N⁺ region in between T₁ and T₂ is kept floating. This structure can confine the kink effect to the upper transistor T₂ and thus successfully keeps the lower transistor T₁ from undergoing pinch-off, impact ionization, and the kink effect. If the channel length of T₁ is longer than that of T₂, then T₁ will dominate the overall output characteristics of the device. As a result, the kink effect is eliminated from the overall output characteristics. This structure can also confine the parasitic bipolar effect only to the upper transistor T₂. Since the base hole current of T₂ will recombine in the common N⁺ region, it cannot reach the base region of the lower transistor T ₁. Results of measurements and simulation are given