Semiconductor apparatus and MIS logic circuit
View Patent ↗A configuration is adopted including an NchMOS transistor ( 1 ) equipped with an insulating isolation layer ( 4 ) providing insulation and isolation using an SOI structure, and a capacitor formed using an insulating film, with a silicon substrate (B) being made thin and substrate capacitance being reduced. The NchMOS transistor ( 1 ) is equipped with insulating isolation regions ( 5 a, 5 b ) that are perfectly depleted or partially depleted in a manner close to being perfectly depleted. An electrode ( 6 ) connected to a gate electrode (G) of the NchMOS transistor ( 1 ) and an impurity diffusion layer ( 7 ) are connected via a capacitor ( 2 ). A source electrode (S) is connected to a power supply terminal ( 3 a ), a gate electrode (G) is connected to an internal signal line (S 1 ), and a drain electrode (D) is connected to an internal signal line (S 2 ). Substrate bias voltage is then controlled using capacitor coupling when the NchMOS transistor ( 1 ) is turned on/off.
1. A semiconductor apparatus forming an insulating isolation region on a silicon substrate of an SOI (Silicon On Insulator) structure, wherein:
the semiconductor apparatus comprises:
a perfectly depleted or close to being perfectly depleted partially depleted-type MIS transistor formed on an electrically insulated silicon substrate surrounded by the insulating isolation region; and
a capacitor formed using an insulating film, wherein the capacitor is configured from a capacitance between metal within a trench formed within the insulating isolation region and the silicon substrate and/or an impurity diffusion layer;
an electrode connected to a gate electrode of the MIS transistor and an impurity diffusion layer formed within the silicon substrate and diffused with the same impurities as the silicon substrate are connected via the capacitor; and
a BJT (Bipolar Junction Transistor) where a drain of the MIS transistor corresponds to a collector, the silicon substrate corresponds to a base, and a source corresponds to an emitter is formed, and where, when gate voltage with respect to the source is V GS , gate capacitance of the MIS transistor is C G , capacitance of the capacitor is C C , parasitic capacitance is C P , clamp voltage of the BJT is V C , and silicon substrate potential immediately prior to change in gate potential is V B(I) , then V B(I) +(C G +C C )*V GS /(C G +C C +C P )>V C .
2. A semiconductor apparatus forming an insulating isolation region on a silicon substrate of an SOI (Silicon On Insulator) structure, wherein:
the semiconductor apparatus comprises:
a perfectly depleted or close to being perfectly depleted partially depleted-type MIS transistor formed on an electrically insulated silicon substrate surrounded by the insulating isolation region; and
a capacitor comprising:
a first capacitor configured using an oxidation film formed between the impurity diffusion layer and the electrode; and
a second capacitor configured using a capacitance between metal within a trench formed within the insulating isolation region and the silicon substrate and/or the impurity diffusion layer;
an electrode connected to a gate electrode of the MIS transistor and an impurity diffusion layer formed within the silicon substrate and diffused with the same impurities as the silicon substrate are connected via the capacitor; and
a BJT (Bipolar Junction Transistor) where a drain of the MIS transistor corresponds to a collector, the silicon substrate corresponds to a base, and a source corresponds to an emitter is formed, and where, when gate voltage with respect to the source is V GS , gate capacitance of the MIS transistor is C G , capacitance of the capacitor is C C , parasitic capacitance is C P , clamp voltage of the BJT is V C , and silicon substrate potential immediately prior to change in gate potential is V B(I) , then V B(I) +(C G +C C )*V GS /(C G +C C +C P )>V C .