JPH06204297A - High frequency semiconductor integrated circuit - Google Patents

Abstract

PURPOSE:To work out a solution about the lack of a low noise oscillation circuit constituted in the same chip with other high frequency circuits and secure isolation properties and constitute a low noise oscillator and a high frequency circuit in the same integrated circuit chip. CONSTITUTION:A die pad 3 on which a chip is loaded and ground terminals 4 and 5 to the outside are not interconnected where there are provided at least one first ground terminal 4 which is not connected to a bonding pad and a substrate frame 10 installed to an area near silicon bipolar integrated circuit by way of aluminum wiring 11 and at least one second ground terminal 5 is provided, which is connected with aluminum wiring 12. The isolation properties are secured by setting the size and structure of a transistor to be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicon bipolar high frequency semiconductor integrated circuit mainly including a high frequency circuit used in a wireless communication device.

[0002]

2. Description of the Related Art A radio communication circuit has conventionally required a high-frequency oscillation circuit, an amplification circuit, etc., and when discrete components are used, the oscillation circuit is usually mounted as another printed circuit board. . In the case of an integrated circuit, in the configuration of a differential type oscillation circuit, there are some examples where the oscillation circuit and the amplification circuit are configured in the same integrated circuit, but in that case, the noise characteristics are inferior and it is intended for wireless communication. Cannot obtain sufficient characteristics. Therefore, it is conceivable to use a silicon bipolar semiconductor process and configure it in a broad sense of Colpitts type as an oscillator circuit for wireless communication, but as in the conventional case, it is of a type directly connected to a substrate. It is difficult to secure the isolation characteristics between the oscillation circuit and other circuits with the configuration in which only a plurality of ground terminals are provided, and the semiconductor integrated circuits are configured as separate semiconductor integrated circuits.

[0003]

However, in the configuration of the differential type oscillation circuit having good isolation characteristics, the noise characteristics are inferior, sufficient characteristics cannot be obtained for wireless communication, and the noise characteristics are excellent. Unlike the differential type, the Colpitts type oscillation circuit in a broad sense has a configuration in which it is easily influenced by the outside and has a great influence on the outside, and in a silicon bipolar integrated circuit having a good noise characteristic. In the case of configuring, in the conventional configuration, the ground terminal has almost common impedance,
There is a problem that a high frequency semiconductor integrated circuit including a low noise oscillation circuit cannot be configured in the same chip because it is difficult to secure the isolation of the ground current between the oscillation circuit and another circuit. It was

The present invention is intended to solve the above-mentioned problems.
The purpose of is to ensure the isolation characteristics by separating the ground of the oscillator and the like, so that a low noise circuit type oscillation circuit can be adopted in the same chip as other high frequency circuits. The second purpose is to reduce mutual influence among a plurality of oscillation circuits included in an integrated circuit. A third purpose is to reduce the capacitance between the substrate of the transistor itself and the size and structure of the transistor while ensuring the isolation characteristics by separating the ground of the oscillator and the like, and reducing the noise, and This is to ensure the isolation characteristics.

[0005]

In order to achieve the above object, the technical solution of the present invention is that the die pad on which the chip is mounted and the ground terminal to the outside are not connected, and the bonding pad and The substrate frame provided near the outer periphery of the silicon bipolar integrated circuit has one or more ground terminals not connected to each other by aluminum wiring, and one or more ground terminals connected to the aluminum wiring, In addition to the unit size transistor, the emitter is divided into unit lengths and a plurality of them are provided in the lateral direction, and the collector and the base extend in the lateral direction in parallel with the emitter, which is larger than the unit size. A transistor is provided.

[0006]

According to the present invention, according to the above structure, first, the ground terminals connected to the frame of the substrate provided around the outer periphery and the aluminum wiring are common ground terminals, and a plurality of the terminals are provided. Signals passing through the substrate are dropped to the ground to ensure isolation characteristics between the terminals, and on top of that, in order to create a ground that is as independent as possible for the high-frequency oscillator circuit in the integrated circuit, the chip is used. Do not connect the die pad to be placed and the ground terminal to the outside to increase the impedance, and by providing a ground terminal that is not connected to the substrate frame and aluminum wiring near the outer periphery to other ground terminals. Isolation characteristics can be secured by configuring so that separate and independent ground terminals can be created. Those were Unishi.

Secondly, in addition to the above, when two or more oscillators for transmission / reception are required, a plurality of ground terminals not connected to the substrate frame near the outer periphery and aluminum wiring are provided. By providing one piece, it is possible to make a plurality of ground terminals that are separate and independent from other ground terminals.

Thirdly, in addition to the above-mentioned first, in addition to the unit size NPN type transistor, a large size NPN type transistor required for oscillation, low noise amplification and power amplification in a high frequency circuit is constructed. When the integrated circuit is viewed from above the chip surface, the emitter is divided into unit lengths and a plurality of them are provided in the lateral direction.
As a structure of an NPN transistor that extends laterally in parallel with the emitter, the total size of the transistors is smaller than that in parallel while the characteristics similar to the case where a plurality of unit transistors are used in parallel are obtained. The capacitance between the straight lines can be reduced, and an improvement effect can be obtained in terms of both the operating frequency and isolation characteristics.

[0009]

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a structural diagram of the inside of bonding of a high frequency semiconductor integrated circuit according to a first embodiment of the present invention.

In FIG. 1, a die pad 3 on which a chip 2 of a silicon bipolar semiconductor integrated circuit having a high-frequency oscillator circuit section 1 is placed, and first and second ground terminals 4 and 5 led to the outside of the integrated circuit. , Try not to connect. In addition, the first bonding pad 6 and the first ground terminal 4 are connected by the first bonding wire 7, and the second bonding pad 8 and the second ground terminal 5 are connected by the second bonding wire 9. Connected by. Further, the ground terminal 4 is used as the ground of the high-frequency oscillator circuit unit 1, and the bonding pad 6 is used.
And a frame 1 for separating the substrate provided around the outer periphery
0 is not connected by the aluminum wiring 11, and the ground terminal 5 is connected by the aluminum wiring 12 between the bonding pad 8 and the frame 10 of the substrate for peripheral separation.

The operation of the above arrangement will be described below. In the form of a semiconductor integrated circuit, it was difficult to ensure both isolation characteristics and noise characteristics at the same time. However, in this embodiment, in an oscillation circuit mainly of Colpitts type having good noise characteristics, isolation due to ground isolation is used. In order to ensure the characteristics, first, the substrate frame 10 and the aluminum wiring 12 provided near the outer periphery are provided.
The ground terminal 5 having the second bonding pad 8 connected to is used as a common ground terminal. On top of that, the substrate on the bottom surface has a resistance component between each point in the chip of the integrated circuit, and each terminal has the reactance of the terminal lead and the inductance of the bonding wire with respect to the ground, and With respect to the substrate, even if the ground is taken outside the integrated circuit due to the capacitance of the bonding pad in the integrated circuit and the resistance component in series with it, low impedance is maintained between the ground terminals. By utilizing what cannot be done in reverse, the high-frequency oscillator circuit unit 1 is integrated in the integrated circuit.
In order to make the ground as independent as possible, the impedance is increased without connecting the die pad 3 on which the chip 2 is mounted and the ground terminals 4 and 5 to the outside, and further, the substrate frame 10 and aluminum wiring near the outer periphery 1
By providing the ground terminal 4 which is not connected by 1 and thickening the line width of the aluminum wiring 11 and using it as the ground of the oscillator, the ground current is separated from the circuit using the other common ground terminal. The route ensures the isolation characteristics.

As is apparent from the above description, according to the present embodiment, it is possible to form a ground terminal separated from other ground terminals, and a high frequency circuit requiring isolation characteristics can be used as a silicon bipolar circuit. It becomes possible to configure with a high frequency semiconductor integrated circuit.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to the same FIG. The third and fourth bonding pads 13 and 14 and the third that is guided to the outside of the integrated circuit,
The fourth ground terminals 15 and 16 are connected by the third and fourth bonding wires 17 and 18. Second
This embodiment differs from the first embodiment in that the third bonding pad 13 and the peripherally separated substrate frame 10 provided in the vicinity of the outer periphery are not connected by aluminum wiring 19 to a high-frequency oscillator circuit. It is to provide one or more third ground terminals 15 for the part 20.
Alternatively, one or more fourth ground terminals 16 for connecting the fourth bonding pad 14 and the peripherally-isolated substrate frame 10 provided near the outer periphery by the aluminum wiring 21 are provided. is there.

The operation of the above arrangement will be described below. When two or more oscillators for transmission / reception are required, etc., the ground terminals 4, 1 of the second embodiment are used.
As in the case of No. 5, in addition to the first embodiment, by providing a plurality of ground terminals which are not connected to the substrate frame 10 near the outer circumference by aluminum wiring, it is possible to separate from other ground terminals. It is possible to form a plurality of ground terminals described above, and for example, two oscillators for transmission and reception can be configured in the same integrated circuit chip. In addition, the ground terminals 5 and 1 of the second embodiment
As in the case of No. 6, in addition to the first embodiment, by providing a plurality of ground terminals connected to the frame 10 of the substrate near the outer periphery and aluminum wiring, the signal component passing through the substrate is eliminated. , It is intended to ensure isolation characteristics between terminals by lowering the impedance to the ground.

As is apparent from the above description, according to this embodiment, it is possible to form a plurality of ground terminals separated from other ground terminals, and in particular, a plurality of ground terminals that require isolation characteristics are required. It is possible to configure a high frequency circuit including an oscillation circuit and the like with a silicon bipolar high frequency semiconductor integrated circuit.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 2 is a basic structural diagram of a transistor portion according to the third embodiment of the present invention. FIG. 2A is a diagram of a transistor portion of a unit size seen from the top surface of the chip,
(B) is a diagram of a large-sized transistor portion viewed from the top surface of the chip, and (c) is a cross-sectional view of a transistor applicable to any of the above sizes. In FIG. 2, when viewed from above the chip surface, a unit size NPN transistor 3 is formed in the high frequency semiconductor integrated circuit as shown in FIG.
0, and when viewed from above the chip surface as in (b), the emitter layer 31 and its electrode 32 shown in (c) are separated into unit lengths and a plurality of them are formed in the lateral direction. The collector electrode 33 and the base electrode 34 are provided, and have an NPN transistor 35 of a size larger than the unit size 30, which has a structure extending in the horizontal direction in parallel with the emitter electrode 32. Further, as shown in FIG. 7C, the transistor 30 and the transistor 35 are the N-type emitter layer 3
1, there is a P-type base layer 36 surrounding it, an N-type collector layer 37 surrounds it, and the lower layer of the collector is a P-type substrate 38. The same sectional view is obtained for (a) and (b).

The operation of the above arrangement will be described below. In addition to the first embodiment, the configuration of the large-sized transistor is as described above, so that the collector 32 and the base 33 are separated in the horizontal direction as compared with the case where the unit-sized transistor 30 is connected in parallel. Therefore, the total size of the transistor can be reduced, and the capacitance can be reduced substantially in proportion to the area between the N-type collector 32 and the P-type substrate 34. Therefore, the operating frequency, the isolation characteristic, which deteriorates due to the capacitance between the collector and the substrate,
The improvement effect can be obtained from any aspect. In addition, it has an advantage that it is easy to study using a plurality of unit-size transistors and to design in consideration of the result. In addition, large size NP
The N-type transistor is necessary in addition to the unit size NPN-type transistor for oscillation, low noise amplification and power amplification in a high frequency circuit.

As is apparent from the above description, according to this embodiment, in addition to the ground separation of the first and second embodiments,
By selecting the transistor structure, while improving the isolation from the transistor such as the oscillation circuit to the substrate, while improving the frequency characteristics, while obtaining the characteristics similar to the case of using multiple unit transistors in parallel for easy characteristics study It is possible to obtain a large size transistor,
In the form of a semiconductor integrated circuit, isolation between the oscillator circuit and other circuits can be ensured.

In the above description, the oscillator circuit is a Colpitts oscillator circuit, but the oscillator circuit may be of any type. Further, if ground separation is required, the invention is not limited to the oscillation circuit, and can be applied to the ground of a power amplification stage, a digital circuit, or the like. Further, not only the silicon bipolar process but also the Bi-CMOS process in which a high frequency circuit and a digital circuit can coexist can be applied.

[0020]

As described above, the present invention does not connect the die pad on which the integrated circuit chip is mounted to the ground terminal, but provides a plurality of independent ground terminals and a plurality of ground terminals connected to the substrate, and has a large size. By selecting the structure of the transistor, it is possible to secure the isolation characteristics with other circuits or other oscillators. Therefore, it is possible to configure a high-frequency circuit requiring isolation characteristics with a silicon bipolar high-frequency semiconductor integrated circuit, and its industrial value for downsizing the device, improving the stability of the characteristics, lowering the cost, etc. large.

[Brief description of drawings]

FIG. 1 is a structural diagram of a bonding inside of a high frequency semiconductor integrated circuit according to first and second embodiments of the present invention.

FIG. 2A is a plan view of a transistor portion of a unit size as seen from the top surface of the chip of the high frequency semiconductor integrated circuit according to the third embodiment of the present invention. FIG. 2B is a plan view of a transistor portion of a large size as seen from the top surface of the same chip. c) A sectional view of a transistor applicable to any of the sizes (a) and (b) of FIG.

[Explanation of symbols]

 1 High Frequency Oscillation Circuit 2 Integrated Circuit Chip 3 Die Pad 4 Ground Terminal 5 Ground Terminal 6 Bonding Pad 7 Bonding Wire 8 Bonding Pad 9 Bonding Wire 10 Substrate Separated Frame 11 Aluminum Wiring 12 Aluminum Wiring 13 Bonding Pad 14 Bonding Pad 15 ground terminal 16 ground terminal 17 bonding wire 18 bonding wire 19 aluminum wiring 20 high frequency oscillation circuit section 21 aluminum wiring 30 unit size transistor 31 emitter layer 32 emitter electrode 33 collector electrode 34 base electrode 35 large size transistor 36 base layer 37 Collector layer 38 Substrate

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location H01L 27/04 E 8427-4M 27/06 H03B 5/24 8124-5J

Claims (6)

[Claims] 1. A second bonding pad having a high-frequency oscillation circuit, wherein a first bonding pad and a first ground terminal led to the outside of the integrated circuit are connected by a first bonding wire. And a second ground terminal led to the outside of the integrated circuit are connected by a second bonding wire, and the first bonding pad in the chip of the integrated circuit and the peripheral isolation provided near the outer periphery are connected. The substrate frame has a first ground terminal not connected to the first aluminum wiring, and the second frame
The bonding pad and the peripherally separated substrate frame have a second ground terminal connected by a second aluminum wiring, and the first aluminum wiring is
A high frequency oscillating circuit is grounded, and the die pad on which the chip of the integrated circuit is mounted and the first and second ground terminals guided to the outside are not connected. Semiconductor integrated circuit. 2. A fourth bonding pad and a fourth ground terminal, which is led to the outside of the integrated circuit, are connected by a fourth bonding wire, and the periphery provided near the outer periphery of the fourth bonding pad. 2. The high frequency semiconductor integrated circuit according to claim 1, wherein the frame of the separated substrate has one or more fourth ground terminals connected to each other by a fourth aluminum wiring. 3. The high frequency semiconductor integrated circuit according to claim 2, comprising a plurality of high frequency oscillation circuits. 4. A third bonding pad and a third ground terminal guided to the outside of the integrated circuit are connected by a third bonding wire, and the third bonding pad and the periphery provided near the outer periphery. 2. The high frequency semiconductor integrated circuit according to claim 1, wherein the frame of the separated substrate has one or more third ground terminals which are not connected to each other by the third aluminum wiring. 5. A high-frequency semiconductor integrated circuit having a unit size transistor, and when the integrated circuit is viewed from above the surface, the emitter is divided into unit lengths and a plurality of electrodes are arranged in the lateral direction. 2. The transistor according to claim 1, wherein the collector and the base are provided in parallel with the emitter in a lateral direction and have a structure of a transistor provided with electrodes, the transistor having a size larger than the unit size. High frequency semiconductor integrated circuit. 6. A high-frequency oscillator circuit according to claim 1,
A high-frequency semiconductor integrated circuit having a high-frequency power amplifier circuit.