Abstract:
A semiconductor device includes a first-conductivity-type semiconductor layer including an active region in which a transistor having impurity regions is formed and a marginal region surrounding the active region, a second-conductivity-type channel layer formed between the active region and the marginal region and forming a front surface of the semiconductor layer, at least one gate trench formed in the active region to extend from the front surface of the semiconductor layer through the channel layer, a gate insulation film formed on an inner surface of the gate trench, a gate electrode formed inside the gate insulation film in the gate trench, and at least one isolation trench arranged between the active region and the marginal region to surround the active region and extending from the front surface of the semiconductor layer through the channel layer, the isolation trench having a depth equal to that of the gate trench.
Abstract:
An improved arrangement is provided for forming a bipolar transistor on a substrate with CMOS elements. All of the transistors (i.e., the bipolar, P-MOS and N-MOS) are formed in regions having gradually decreasing impurity concentrations from the surface toward the substrate. In addition, a buried layer is provided under each of the regions of decreasing impurity concentration in which the transistors are formed. These buried layers have a significantly higher impurity concentration than the portion of the region of decreasing impurity concentration which they are respectively adjacent to. Using this arrangement, punch-through is prevented and excellent electrical operating characteristics are provided for both the bipolar transistors and the CMOS elements.
Abstract:
The invention provides a Bi-CMOS gate array semiconductor integrated circuit chip including a peripheral region including an input/output circuit region and a bonding pad region and an internal cell structure provided within an internal cell region involved in the semiconductor integrated circuit chip. The internal cell structure comprises MOS transistor cell units including a plurality of MOS transistors and bipolar transistor cell units including a plurality of bipolar transistors wherein a distribution ratio in the number of the MOS transistor cell units to the bipolar transistor cell units has such a variation that the distributed ratio is high in a region that requires driving of almost no or a small load while the distributed ratio is low in a region that requires driving of a large load.
Abstract:
An improved cell for use in a mask programmable gate array is disclosed herein. The preferred cell comprises two compute sections, each comprising two pairs of medium size P and N-channel transistors, two small N-channel transistors, and a single small P-channel transistor. Each cell also comprises a high efficiency drive section containing a single bipolar pull-up transistor, a large N-channel pull-down transistor, and a small P-channel transistor. By using this cell, an extremely high compute capability per die area is achieved.
Abstract:
A logic circuit to be formed in a gate array is selected depending upon the value of the output load capacitance thereof, from among a CMOS circuit, a first Bi-CMOS circuit including an output bipolar transistor whose emitter size is set at a predetermined value, and a second Bi-CMOS circuit including an output bipolar transistor whose emitter size is larger than the emitter size of the output bipolar transistor of the first Bi-CMOS circuit. That is, the logic circuit is brought into a circuit form whose output load capacitance can be charged and discharged fastest. As a result, the logic circuit constructed in the gate array by adopting such a design technique has its operating speed raised. An improved structure is also provided for reducing wiring lengths by arranging bipolar transistors in adjacent basic cells to have mirror symmetry with one another. Further, particular gate width relationships are provided between MOSFETs within basic cells for reducing propagation delay and the required occupation area.
Abstract:
A semiconductor device includes a first-conductivity-type semiconductor layer including an active region in which a transistor having impurity regions is formed and a marginal region surrounding the active region, a second-conductivity-type channel layer formed between the active region and the marginal region and forming a front surface of the semiconductor layer, at least one gate trench formed in the active region to extend from the front surface of the semiconductor layer through the channel layer, a gate insulation film formed on an inner surface of the gate trench, a gate electrode formed inside the gate insulation film in the gate trench, and at least one isolation trench arranged between the active region and the marginal region to surround the active region and extending from the front surface of the semiconductor layer through the channel layer, the isolation trench having a depth equal to that of the gate trench.
Abstract:
A semiconductor device includes a first-conductivity-type semiconductor layer including an active region in which a transistor having impurity regions is formed and a marginal region surrounding the active region, a second-conductivity-type channel layer formed between the active region and the marginal region and forming a front surface of the semiconductor layer, at least one gate trench formed in the active region to extend from the front surface of the semiconductor layer through the channel layer, a gate insulation film formed on an inner surface of the gate trench, a gate electrode formed inside the gate insulation film in the gate trench, and at least one isolation trench arranged between the active region and the marginal region to surround the active region and extending from the front surface of the semiconductor layer through the channel layer, the isolation trench having a depth equal to that of the gate trench.
Abstract:
A bipolar transistor/insulated gate transistor hybrid semiconductor device comprises a well region formed on a semiconductor substrate to serve as a first active region of a bipolar transistor, an insulated gate transistor having source and drain regions formed in the well region, which acts as a back gate of the insulated gate transistor, and second and third active regions of the bipolar transistor formed in the well region. At least one of the second and third active regions is used in common to one of the source and drain regions of the insulated gate transistor. A plurality of well regions is regularly arranged to constitute a gate array.
Abstract:
In a semiconductor integrated circuit device adopting a master slice system, a plurality of lattice points of an X-Y lattice-shaped channel region set by an automatic arrangement and routing system correspond to one input/output terminal of a prescribed basic cell (or logic circuit), thereby a plurality of signal wirings can be connected to the one input/output terminal.
Abstract:
A method for manufacturing a Bi-CMOS device by preparing both of bipolar and MOS standard cells in a library is provided. A substrate of a first conductivity type is provided and a plurality of buried layers of a second conductivity type are formed on selected locations of the substrate. Then an epitaxial layer of the first conductivity type is formed on the substrate covering the buried layers. Then a plurality of wells of the second conductivity type are formed in the epitaxial layer such that each of the wells extends through the epitaxial layer from the top surface to at least a portion of the corresponding buried layer to thereby define a plurality of electrically isolated islands in the epitaxial layer. Then a bipolar transistor is formed in at least one of the islands with a MOS transistor formed in at least another of the islands.