Abstract:
A semiconductor device has a semiconductor substrate, a first insulating film formed on a surface of the semiconductor substrate, a first recess formed in the first insulating film, a first barrier film formed on an inner surface of the first insulating film except a top peripheral region of the first trench, a first conductive film formed in the first trench, and a covering film formed on an upper surface and a top peripheral region of the first conductive film and an upper surface of the first barrier film. The first conductive film includes copper.
Abstract:
The wiring structure of a semiconductor device of the invention enhances the dielectric strength of the wirings and reduces the capacitance across the wirings, by preventing a diffusion of the wiring material. The wiring structure includes a first insulating film, plural wiring films, plural barrier films, and plural cap films. The first insulating film has plural grooves formed thereon, and has an interface in the horizontal direction between the adjoining grooves. The wiring films are formed to protrude from the interface each by the grooves of the first insulating film. The barrier films are formed on the bottoms of the wiring films, and also on side faces of the wiring films to a height exceeding the interface. The cap films are formed at least on the upper faces of the wiring films, and are separated each by the grooves.
Abstract:
A high frequency filter comprises thin film piezoelectric resonators connected in series between the input/output nodes, thin film piezoelectric resonators connected in parallel between the input/output nodes and a variable voltage circuit adapted to change the voltage applied to at least either the thin film piezoelectric resonators connected in series or the thin film piezoelectric resonators connected in parallel. The resonance characteristic of at least either the thin film piezoelectric resonators connected in series or the thin film piezoelectric resonator connected in parallel is shifted by changing the voltage applied by the variable voltage circuit to change the pass characteristic of the filter.
Abstract:
To provide a miniaturized voltage controlled oscillator which can oscillate simultaneously a plurality of frequencies and has high stability of frequency, an excellent low phase noise, small variation per hour, and a wide frequency variable range. A thin film bulk acoustic wave resonator using single crystal ferroelectric material equal to or smaller than 10 &mgr;m in thickness whose direction of polarization is aligned to the direction of thickness is utilized as the piezoelectric member. The voltage controlled oscillator having large changing rate of the oscillation frequency of 0.01%/V or more and an extremely small phase noise is provided by changing the voltage applied to the electrodes.
Abstract:
Before deposition of a CVD titanium film on a cobalt silicide layer, an element which reacts with titanium is provided in the cobalt silicide layer in advance. Thereafter, the CVD titanium film is deposited on the cobalt silicide using a titanium tetrachloride gas.
Abstract:
A semiconductor memory device is constituted by arranging a plurality of memory cells in a matrix format, each of which includes a thin-film capacitor having a ferroelectric film and a pair of electrodes facing each other via the ferroelectric film, and a transfer gate transistor connected to the thin film capacitor. A voltage corresponding to the width of a hysteresis curve obtained when the thin-film capacitor is saturated and polarized falls within the range of 5% or higher to 20% or lower of the voltage difference between the positive and negative directions in a writing operation. A remanent polarization amount obtained when the thin-film capacitor is saturated and polarized falls within the range of 5% or higher to 30% or lower of the total polarization amount obtained upon application of a voltage in the writing operation.
Abstract:
A semiconductor device has a semiconductor substrate, a first insulating film formed on a surface of the semiconductor substrate, a first recess formed in the first insulating film, a first barrier film formed on an inner surface of the first insulating film except a top peripheral region of the first trench, a first conductive film formed in the first trench, and a covering film formed on an upper surface and a top peripheral region of the first conductive film and an upper surface of the first barrier film. The first conductive film includes copper.
Abstract:
According to an embodiment, the present invention provides a semiconductor device that is easily integrated with other electronic circuits and functions as an oscillator with high frequency accuracy. The semiconductor device includes: a semiconductor substrate; an element region; an element isolation region that surrounds the element region; a field effect transistor including a gate electrode that is formed on the element region, source and drain regions, and a channel region that is interposed between the source region and the drain region; gate, source, and drain terminals that are used to apply a voltage to the gate electrode, the source region, and the drain region, respectively; and an output terminal that is electrically connected to the channel region. When the threshold voltage of the field effect transistor is Vth, a gate voltage Vgs applied between the source terminal and the gate terminal and a drain voltage Vds applied between the source terminal and the drain terminal satisfy the following relationship: Vth
Abstract:
A power amplifier according to the embodiments includes: a silicon substrate; an input terminal configured to receive an input of a RF signal; a power dividing unit configured to divide the RF signal into a first signal and a second signal; a phase modulating unit configured to modulate a phase of the second signal; an N well formed in the silicon substrate; a P well formed in the N well and configured to receive an input of the second signal of a modulated phase; a gate insulating film formed on the P well; a gate electrode formed on the gate insulating film and configured to receive an input of the first signal; source and drain electrodes formed on both sides of the gate electrode in the silicon substrate; and an output terminal configured to output a RF signal obtained from the drain electrode.
Abstract:
According to an embodiment, a power amplifier is provided with at least one first growth ring gate structure and multiple second growth ring gate structures. The first growth ring gate structure is bounded by a semiconductor layer and performs a power amplification operation. The multiple second growth ring gate structures are bounded by the semiconductor layer and are arranged adjacently around the first growth ring gate structure in a surrounding manner. When the first growth ring gate structure performs a power amplification operation, the multiple second growth ring gate structures are depleted by applying a reverse bias to the multiple second growth ring gate structures whereby the depleted multiple second growth ring gate structures isolate the first growth ring gate structure from a surrounding portion.