Abstract:
In a semiconductor device manufacturing method, an amorphous or microcrystalline metal oxide film is formed over a first metal film which is preferentially oriented along a predetermined crystal plane. After that, a ferroelectric film is formed by a MOCVD method. When the ferroelectric film is formed, the metal oxide film formed over the first metal film is reduced to a second metal film and the ferroelectric film is formed over the second metal film. When the ferroelectric film is formed, the amorphous or microcrystalline metal oxide film is apt to be reduced uniformly. As a result, the second metal film the orientation of which is good is obtained and the ferroelectric film the orientation of which is good is formed over the second metal film. After the ferroelectric film is formed, an upper electrode is formed over the ferroelectric film.
Abstract:
The transistor comprises a source (1) and a drain (2) separated by a lightly doped intermediate zone (I). The intermediate zone (I) forms first (3) and second (4) junctions respectively with the source (1) and with the drain (2). The transistor comprises a first gate (5) to generate an electric field in the intermediate zone (I), on the same side as the first junction (3), and a second gate (6) to generate an electric field in the intermediate zone (I), on the same side as the second junction (4).
Abstract:
A process for forming a capacitor with a high-k dielectric or ferroelectric layer within a semiconductor device is used to reduce the likelihood of oxidation or materials interactions between that layer and an underlying layer. A first electrode layer includes atoms that form along grain boundaries within the first electrode layer to reduce the oxidation of a conductive plug or undesired materials interactions.
Abstract:
A semiconductor device having a semiconductor substrate of a first conductivity type, an epitaxial layer of a second conductivity type formed on a major surface of the semiconductor substrate, an isolation layer of the first conductivity type formed in the epitaxial layer and extending from a surface thereof to the major surface of the semiconductor substrate. The isolation layer divides the epitaxial layer into first, second, and third islands. The device further has two wells of the first conductivity type, formed in the first and second islands, respectively, and extending to the substrate, a charge transfer device having a back gate formed of the first well, an insulated-gate FET of the first conductivity type, having a back gate formed of the second island, an insulated-gate FET of the second conductivity type, having a back gate formed of the second well, and a bipolar transistor having a collector formed of the third island. The first island surrounds the first well which serves as back gate of the charge transfer device, and thus blocks the noise generated in the first well. Hence, the other islands are free from the influence of the noise.
Abstract:
The specification describes a high capacity nonvolatile CCD read only memory system that includes a plurality of memory cells. Selected ones of the memory cells include a double-diffused region having a first and second implant or diffusion under a clocked electrode whereby the first implant or diffusion provides a fixed charge required for ROM operation and the charge and polarity of said second implant or diffusion provides a neutralizing effect on the surface potential under the clocked electrode and above the double implanted or double diffused region.
Abstract:
The present invention involves a semiconductor device, such as a shift register, wherein information in the form of charge carriers is moved laterally through the bulk of a semiconductor layer by means of an electric field, while the charge carriers are stored at the surface of the semiconductor layer. According to this invention, information containing regions can be separated from each other by depletion zones extending through the thickness and the width of the semiconductor layer. Charge transport laterally through the interior of the semiconductor layer results in a considerable reduction of the transport time. Majority charge carriers are advantageously used.
Abstract:
An integrated rectifier circuit has a doped semiconductor body having first and second oppositely doped regions therein and is covered by an electrically insulating layer on which a first pair of input gate electrodes are disposed which are associated with the first oppositely doped region and on which a second pair of input gate electrodes are disposed associated with the second oppositely doped region. The oppositely doped regions are connected to a clock pulse voltage and all of the input gate electrodes are connected to a constant voltage having a magnitude such that a uniform surface potential exists in the semiconductor regions covered by the electrodes. The input gate electrode of the first pair which is disposed at a greater distance from the first oppositely doped region and the input gate electrode of the second pair which is disposed closer to the second oppositely doped region are charged with the alternating voltage component of an input signal. A charge transfer device transfer channel covered with transfer electrodes is connected to the semiconductor regions covered by the input electrodes and a charge transfer device output stage couples an output signal to external circuitry in which the alternating voltage component is rectified.
Abstract:
A charge coupled device memory is disclosed which includes a plurality of stages having increased charged storage capacity and decreased leakage current. Each stage is comprised of a semiconductor substrate of a first-type conductivity having a first surface. An insulating layer of uniform thickness lies on the first surface. A charge transfer channel extends through each stage. Phase electrodes lie on the insulating layer transversely to the channel. The semiconductor substrate under the phase electrodes is divided into barrier regions and adjacent well regions bounded by the channel. A dopant layer of a second-type conductivity lies in each of the well regions relatively near to the first surface. An enhanced first-type conductivity dopant layer lies in the well regions and the barrier regions relatively far from the surface having a doping which is greater than the doping of the first-type conductivity semiconductor substrate.
Abstract:
A filter utilizing charge transfer devices for providing recursive transfer functions with a transmission zero at d.c. or zero frequency is described. The filter includes a circular charge transfer shift register having an even number N of stages, greater than two, and first, second, third and fourth linear charge transfer shift registers. All five shift registers are clocked at the same frequency. A first input sequence of packets of charge representing positive weight components of a signal, and a second sequence of packets of charge representing negative weight components of the signal are provided. Means are provided for dividing each of the packets of charge of the first input sequence into a first part and a second part and for applying each of the first parts of the packets of the first input sequence to the input stage of the first shift register and for applying each of the second parts of the packets of the first input sequence to the input stage of the second shift register. The charge packet in the first charge storage cell in the K.sup.th stage of the first shift register is combined with the charge packet in the first charge storage cell of the N.sup.th stage of the circular shift register. The combined packet of charge is divided into two portions, a first portion being stored in the first charge storage cell of the K.sup.th stage of the first shift register from which it is clocked out and sensed and a second portion being stored in the first charge storage cell of the N.sup.th stage of the circular shift register. The charge packet in the first charge storage cell of the L.sup.th stage of the second shift register is combined with the charge packet in the M.sup.th stage of the circular shift register, where M is an integer less than N/2 and L=K+M.Means are provided for dividing each of the packets of charge of the second input sequence into a first part and a second part and for applying each of the first parts of the packets of the second input sequence to the input stage of the third shift register and for applying each of the second parts of the packets of the second input sequence to the input stage of the fourth shift register. The charge packet in the first charge storage cell in the K.sup.th stage of the third shift register is combined with the charge packet in the first charge storage cell of the (N/2).sup.th stage of the circular shift register. The combined packet of charge is divided into two portions, a first portion being stored in the first charge storage cell of the K.sup.th stage of the third shift register from which it is clocked out and sensed and a second portion being stored in the first charge storage cell of the (N/2).sup.th stage of the circular shift register. The charge packet in the first charge storage cell of the L.sup.th stage of the fourth shift register is combined with the charge packet in the (N/2+M).sup.th stage of the circular shift register.A first output sequence of packets of charge representing the positive components of an output signal is obtained at the output of the first shift register. A second output sequence of packets of charge representing the negative components of the output signal is obtained at the output of the second shift register. The output signal is obtained by differentially summing corresponding charge packets in the first and second output sequences.
Abstract:
Disclosed is a charge transfer device, like a transversal filter, having means for detecting if an amount of signal charge transferred from one stage to another falls within a dynamic range of the device. A charge transfer channel is so formed as to have first and second branched output ports. A signal charge transferred to the first output port is detected as an output signal supplied to a utilization circuit while an output voltage caused by a signal charge transferred to the second output port is compared with first and second reference voltages which correspond to first and second amounts of signal charges substantially determining upper and lower limits of the dynamic range of the device, whereby it is detected if the amount of the signal charge transferred is within the dynamic range or not. As a result of the detection when the signal charge amount is outside the dynamic range, the supply of the output signal to the utilization circuit is interrupted.