US 7,923,737 B2Granted

Three-terminal switch array device, combined semiconductor device, and image forming apparatus

AssigneeOki Data Corporation

InventorAkira Nagumo

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Abstract

A combined semiconductor device can be formed by bonding the thin-film three-terminal switching elements to a surface of an integrated circuit chip including a shift register that shifts data supplied to the control electrodes of the three-terminal switching elements, or by bonding both the thin-film three-terminal switching elements and another thin semiconductor film including the shift register to a substrate. In either case, thin-film wiring can be used to interconnect the shift register and the switching elements, and the need for an array of large transistors to feed driving current to the switching elements is eliminated, reducing the size and cost of the combined semiconductor device, which can be advantageously used in the optical head of an electrophotographic printer.

Claims15

Dependent claims

A combined semiconductor device comprising:

a substrate comprised of crystalline silicon, the substrate including a first surface;
a dielectric film bonded to the first surface of the substrate;
a three-terminal switch array having a plurality of three-terminal light-emitting switching elements formed from a thin semiconductor film comprised of a compound semiconductor, the three-terminal light-emitting switching elements being arranged in an array from a first three-terminal light-emitting switching element to an N-th three-terminal light-emitting switching element on the first surface of the substrate, N being an integer greater than unity, each three-terminal light-emitting switching element having a first electrode, a second electrode, and a control electrode, and wherein the thin semiconductor film is bonded to the dielectric film such that the dielectric film is between the substrate and the three-terminal switch array;
a shift register circuit with first to N-th output terminals for output of logic signals, N being an integer greater than unity;
wherein the shift register circuit is formed in the substrate;
a driving controller outputting driving current in synchronization with output of the logic signals from the shift register circuit;
a ground electrode;
a layer of control electrode wiring formed from a thin film, the control electrode wiring conducting the logic signal from the N-th output of the shift register circuit to the control electrode of the N-th three-terminal light-emitting switching element, for each integer N from one to N, and extending along the first surface of the substrate and a surface of the thin semiconductor film;
a layer of power-supply wiring formed from a thin film, the power-supply wiring connecting the first electrode of each three-terminal light-emitting switching element to the driving controller, and extending along the first surface of the substrate and the surface of the thin semiconductor film;
and
a layer of ground wiring formed from a thin film, the ground wiring connecting the second electrode of each three-terminal light-emitting switching element to the ground electrode, and extending along the first surface of the substrate and the surface of the thin semiconductor film.

8 more elements

A combined semiconductor device comprising:

a semiconductor substrate comprised of crystalline silicon;
a dielectric film bonded to a first surface of the semiconductor substrate;
a shift register circuit formed in the semiconductor substrate, the shift register having a plurality of output terminals;
a plurality of three-terminal elements formed in a thin semiconductor film comprised of a compound semiconductor bonded to the semiconductor substrate and arranged in a direction parallel to a direction in which the output terminals of the shift register are arranged, each three-terminal element having a first electrode, a second electrode, and a control electrode, the three-terminal elements emitting light by conducting current between their first and second electrodes when switched on by their control electrodes, and wherein the thin semiconductor film is bonded to the dielectric film such that the dielectric film is between the semiconductor substrate and the plurality of three-terminal elements;
a layer of control electrode wiring formed from a thin film, the control electrode wiring connecting the control electrodes of the three-terminal elements to respective output terminals of the shift register, and extending along the first surface of the semiconductor substrate and a surface of the thin semiconductor film;
a layer of power-supply wiring formed from a thin film, the power-supply wiring interconnecting the first electrodes of the three-terminal elements, and extending along the first surface of the semiconductor substrate and the surface of the thin semiconductor film;
and
a layer of ground wiring formed from a thin film, the ground wiring interconnecting the second electrodes of the three-terminal elements, and extending along the first surface of the semiconductor substrate and the surface of the thin semiconductor film.

5 more elements

A combined semiconductor device comprising:

a substrate comprised of a glass or a ceramic;
a dielectric film bonded to a first surface of the substrate;
a shift register formed in a first thin semiconductor film comprised of polysilicon or an organic semiconductor, and bonded to the substrate, the shift register having a plurality of output terminals;
a plurality of three-terminal elements formed in a second thin semiconductor film bonded to the dielectric film such that the dielectric film is between the substrate and the plurality of three-terminal elements, and arranged in a direction parallel to a direction in which the output terminals of the shift register are arranged, each three-terminal element having a first electrode, a second electrode, and a control electrode, the light-emitting elements emitting light by conducting current between their first and second electrodes when switched on by their control electrodes, the second thin semiconductor film comprised of a compound semiconductor;
a layer of control electrode wiring formed from a thin film, the control electrode wiring connecting the control electrodes of the three-terminal elements to respective output terminals of the shift register, and extending along surfaces of the first and second thin semiconductor films;
a layer of power-supply wiring formed from a thin film, the power-supply wiring interconnecting the first electrodes of the three-terminal elements, and extending along the surfaces of the first and second thin semiconductor films;
and
a layer of ground wiring formed from a thin film, the ground wiring interconnecting the second electrodes of the three-terminal elements, and extending along the surfaces of the first and second thin semiconductor films.

5 more elements

Dependencies are inferred from the claim text.