JPH0440270Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a transistor device, and particularly to a circuit unit in which a thin film resistor is formed on a transistor chip.

In electronic equipment such as video tape recorders, which are composed of a combination of various electronic circuits, there are cases in which it is disadvantageous in terms of functionality to convert the component circuits into integrated circuits (ICs), or there are cases in which it is difficult to convert them into ICs due to the setting of circuit constants, etc. It can be difficult. Generally, in ICs, diffused resistance is used as a resistance element to form multiple transistors, but since each element is electrically separated from other elements by isolation, the existence of parasitic transistor effects is ignored. Can not do it. In addition, in general, ICs use transistors with good high frequency characteristics, transistors with fast switching speed,
Alternatively, it is difficult to form transistors with high breakdown voltage and large current. For this reason, in electronic devices that include circuits that are not suitable for IC implementation, circuits are constructed using individual components such as transistors and chip resistors.
The components are mounted on a printed circuit board along with ICs and other components.

FIGS. 1 and 2 show transistor circuits made up of individual components. FIG. 1 shows a relay drive circuit, in which a transistor circuit 2 as a switching circuit is installed. That is, an input terminal 8A is formed at the base of the transistor 4 via a resistor 6, an input terminal 8B is formed at the emitter, and a resistor 10 is connected between the emitter and the base. Input terminal 8B is reference potential point (GND) terminal 8
It is common with C. Further, between the collector of the transistor 4 and the voltage application terminal 12, an exciting coil 14A of the relay 14 and a diode 16 are connected in parallel.
is connected. In this relay drive circuit, the input voltage applied between input terminals 8A and 8B
By switching the transistor using Vi, the excitation current of the excitation coil 14A of the relay 14 is controlled, and its contact 14B opens and closes.

Furthermore, FIG. 2 shows an inverter circuit installed at the interface, in which a transistor circuit 2 is installed, a resistor 18 is connected in place of the relay 14 and the diode 16, and an output terminal is connected to the collector of the transistor 4. 20 was formed. That is, in this inverter circuit, the voltage Vi input to the input terminals 8A and 8B
is inverted by transistor 4 and taken out from output terminal 20.

In this way, in the relay drive circuit and the inverter circuit, although the transistor circuit 2 has different functions depending on its use, its configuration is the same. When forming such a circuit with individual components,
The mounting area of the printed circuit board is large, which increases the number of wiring steps and prevents the miniaturization and weight reduction of electronic devices. Electronic devices such as video tape recorders that include multiple circuits of this type become expensive.

Therefore, the object of this invention is to provide a transistor device in which a resistor associated with a transistor is placed on a semiconductor substrate which constitutes a collector of the transistor, thereby forming a three-terminal circuit element consisting of a transistor and a resistor.

That is, the transistor device of this invention uses the minimum number of semiconductor substrates 3 that can form a single transistor.
2, this semiconductor substrate is used as a collector, a first conductive region selectively formed on the semiconductor substrate is a base 34, and a second conductive region selectively formed inside this base is an emitter. A single transistor 24 of 36 is installed, and a first resistor 26 and a second resistor 30 made of thin film resistors are installed on an insulating layer (oxide film 38) covering this transistor. One end is connected to the base with a wiring conductor (electrode 42), and the second resistor is connected between the base and emitter of the transistor with a wiring conductor (emitter electrode 40), and the collector terminal 28C is connected to the semiconductor substrate. ,
An emitter terminal 28E is connected to the emitter, and a base terminal 28 to the base is connected to the other end of the first resistor.
B.

Hereinafter, this invention will be described in detail with reference to embodiments shown in the drawings.

3 to 5 show embodiments of the transistor device of this invention, FIG. 3 shows the circuit of the transistor device, FIG. 4 shows the structure of the surface portion of the transistor device without a protective film, and FIG. 4 shows a cross section taken along line VV in FIG. 4.

As shown in FIG.
2 uses the transistor circuit 2 shown in FIGS. 1 and 2 as a circuit unit, and its constituent elements are combined into a single device similar to the transistor 4. That is, this transistor device 2
2 is provided with a transistor 24, a terminal 28B is formed at the base of this transistor 24 via a first resistor 26, and a second resistor 30 constituting a bias circuit is connected between the base and emitter. There is. Terminals 28E and 28C are individually formed on the emitter and collector.

This transistor device 22 is configured as shown in FIGS. 4 and 5, and has a minimum semiconductor substrate capable of forming a single transistor.
A base 34 of a single transistor 24 is formed on the surface layer of a semiconductor substrate 32 made of silicon or the like, and an emitter 36 is formed on this base 34. This transistor 24 is formed similarly to a conventional transistor as a discrete component.

Further, on the surface of the oxide film 38 formed of SiO ₂ or the like as an insulating layer covering the surface part of the semiconductor substrate 32,
A thin film resistor is formed of Ni-Cr or polysilicon by vacuum evaporation or the like, and this thin film resistor resistor 26,
30 are configured. Then, a contact window is formed in the oxide film 38 covering the surface of the emitter 36, and aluminum, gold, etc. is vapor-deposited to form the electrode 40.
is formed. This electrode 40 is extended as a wiring conductor to the upper surface of the end of the resistor 30 and is electrically connected. Further, a contact window is formed in the oxide film 38 covering the surface of the base 34, and an electrode 42 is formed in the same manner as the electrode 40. This electrode 42 is extended as a wiring conductor to the upper surface of one end of the resistors 26 and 30, and is electrically connected.

An electrode 44 is formed at the end of the resistor 26 so as to face the electrode 42 . The semiconductor substrate 32 serves as a collector, and the terminal 28C is formed on the semiconductor substrate 32. In addition, each electrode 4
Terminals (pins) 28B and 28E formed on a container housing the semiconductor substrate 32 are electrically connected to terminals 0 and 44 by lead bonding.

This transistor device 22 is formed in one package like a conventional single transistor. That is, transistor 24 and resistor 2
The circuit unit consisting of 6 and 30 has three terminals like a normal transistor, and can be handled like a transistor as an individual component.
Furthermore, since the electrical characteristics of the transistor 24 and the resistance values of the resistors 26 and 30 can be arbitrarily formed depending on the application, the present invention can be applied to various applications such as switching circuits and inverter circuits.

In particular, since the transistor 24 and the resistors 26 and 30 are integrated into one chip, there is no need to connect the resistor externally compared to the conventional circuit configuration in which the resistor is externally connected to the transistor, which simplifies the wiring process. At the same time, it is possible to reduce the size and weight of various devices used, and in particular, it is possible to reduce the mounting cost of printed circuit boards. In terms of circuit configuration, since the resistor 26, which is the base input resistance, is formed inside the package of the transistor 24, the withstand voltage against external surges, static electricity, etc. is improved, and since the base is not drawn out, external It is less susceptible to the effects of noise, and can easily and simply form high-voltage, large-current circuits that cannot be formed with ordinary ICs.

Furthermore, the transistor 24 constituting the circuit unit has small emitter-base and base-collector stray capacitances, and can improve frequency characteristics, switching speed, etc.
It is possible to achieve superior properties that cannot be obtained with other methods. Also, compared to an IC, there is no reference potential point (GND) terminal, so the transistor 24
The base terminal can be biased below the emitter potential without being restricted to use with the emitter grounded. Moreover, according to such a transistor device 22, a complementary device having the same characteristics can be easily achieved.

The transistor device 22 also includes a resistor 26,
Since 30 is formed of a thin film resistor, isolation in the IC is unnecessary, and parasitic transistor effects do not occur, so there is no need to take countermeasures.

In addition, although the case of an NPN type transistor was explained in the embodiment, the same effect can be obtained with a PNP type transistor. Furthermore, regarding the configuration of the circuit unit, this idea can be applied to basic circuits or special circuits, so it is not limited to a format consisting of a single transistor, and the number of terminals can be changed depending on the purpose. Can be set.

As explained above, according to this invention, a single transistor is installed on the minimum semiconductor substrate on which a single transistor can be formed, and the first and second resistors are installed on the upper surface of the insulating layer covering the transistor. Since the transistor device is constructed as a three-terminal circuit element similar to a transistor, it can be widely applied as a circuit unit to various electronic circuits, such as switching circuits, inverters, amplifier circuits, etc., and is compact and lightweight, reducing wiring man-hours. It is possible to provide circuit elements that cannot be obtained with individual components or integrated circuits, such as reduction in energy consumption, high withstand voltage, and large current.

[Brief explanation of the drawing]

1 and 2 are circuit diagrams showing a transistor circuit using individual components, FIG. 3 is a circuit diagram showing an embodiment of the transistor device of this invention, FIG. 4 is a plan view showing its configuration, and FIG. The figure is a sectional view taken along the line V-V in FIG. 4. 22...Transistor device, 24...Transistor, 26...First resistor, 28B...Base terminal, 28E...Emitter terminal, 28C...Collector terminal, 30...Second resistor, 32...Semiconductor substrate , 34...Base, 36...Emitsuta, 38...
...Oxide film (insulating layer), 40... Emitter electrode (wiring conductor), 42... Electrode (wiring conductor)

Claims (1)

[Scope of utility model registration request] A minimum semiconductor substrate capable of forming a single transistor is installed, this semiconductor substrate is used as a collector, a first conductive region selectively formed on the semiconductor substrate is used as a base, and a selective conductive region is formed inside the base. A single transistor having an emitter formed in a second conductive region formed in Connecting one end of the resistor to the base with a wiring conductor,
The second resistor is connected between the base and the emitter of the transistor by a wiring conductor, a collector terminal is connected to the semiconductor substrate, an emitter terminal is connected to the emitter, and a base terminal connected to the base is connected to the other end of the first resistor. A transistor device comprising: