JPH0585091A - Semiconductor device - Google Patents

Abstract

(57) [Summary] [Structure] The pad portion 6 is formed on the surface of the semiconductor integrated circuit chip 1 including the memory 2, the address counter 3, the oscillator 4 and the like.
By including the shield ring 5 made of a conductive material serving as an electrostatic shield material, the shield is performed inside the semiconductor integrated circuit. [Effect] By applying the semiconductor device having the semiconductor integrated circuit chip therein to, for example, an IC card, it is possible to eliminate a failure caused by an induced current due to a strong electric field or discharge including a dynamic change of static electricity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device applied to an IC card or the like.

[0002]

2. Description of the Related Art In recent years, an IC card having an IC, a so-called semiconductor integrated circuit, inside a card-shaped structure has been receiving attention. The IC card is used for various purposes. For example, it is formed into a tag (tag) to be used for recognition of articles in a distribution system, or formed into a card (personal identification tag) as a gate, etc. It is used for checking in security systems such as entry and exit management. Among IC cards, non-contact by microwave I
C cards So-called microwave cards include reflection type or active type. The reflection type IC card is provided with an antenna for reflecting a radio wave in the main body, and the radio wave transmitted from the recognition device is reflected by the antenna and sent back to the recognition device. Further, the active IC card is configured to receive a radio wave from the recognition device, generate and transmit a recognition data signal corresponding to the radio wave in each circuit, and send the data signal back to the recognition device.

As the reflection type IC card, the present applicant has previously proposed a non-contact type IC card using microwaves, a so-called microwave card, in the specification and drawings of JP-A-1-18272. The schematic configuration in this proposal is, for example, an antenna that reflects an incident microwave of 2.45 [GHz], a transmission data generation circuit, an impedance change circuit that changes the impedance of the antenna corresponding to the transmission data, and a battery. And transmitting data by utilizing the fact that the reflection characteristic of the antenna changes according to the change of the impedance of the antenna. With this configuration, the IC card can be made extremely thin. Here, the transmission data generating circuit and the impedance changing circuit are configured as a so-called identification code generator by a semiconductor integrated circuit (IC) in which an oscillator, an address counter, a memory, and an FET transistor are integrally incorporated. There is.

[0004]

By the way, in general, I
In C, the input / output terminal is protected by a transistor structure including a diode and a substrate, but a means for preventing a failure caused by an inductive current caused by a strong electric field or a discharge including a dynamic change of static electricity in proximity. Was not done in the IC. In addition, some CMOS (Complementary MO
S) has a low carrier concentration (large resistance value) and is easily charged up after impact by a strong electric field or the like, so that a so-called sleep phenomenon in which the circuit operation is stopped for a while easily occurs.

Further, of the above IC cards having an IC inside the card structure, for example, the microwave card has a thin structure of about 1 mm obtained by bonding the IC onto a glass epoxy substrate. It is easy to apply an electric field that exceeds the order of magnitude of 2-3 kv / mm, which causes physical damage. On the other hand, even if a shield structure is applied to the card structure, it can only withstand an electric field of about 10 kv / mm. this is,
The amount of static electricity in a general environment is
Human body (capacitance 10
When static electricity is discharged from (0 to 300 pF), the electrostatic charging voltage generally reaches 12 kv for a person walking on a carpet and 4 kv for a person walking on a floor of vinyl tile, and the maximum electrostatic charging voltage in the above cases. Is a problem when considering that it reaches 13 to 39kv.

In view of the above problems, it is an object of the present invention to provide a semiconductor device which prevents a memory loss change due to static electricity or an induced current including a dynamic change, a circuit malfunction and an element destruction.

[0007]

A semiconductor device according to the present invention is a semiconductor device having a semiconductor integrated circuit chip therein, wherein a conductive material serving as a ring-shaped electrostatic shield material is provided around the surface of the semiconductor integrated circuit chip. The above-mentioned problems are solved by forming and depositing.

[0008]

In the semiconductor device according to the present invention, a conductive material serving as an electrostatic shield material is applied to the periphery of the surface of the semiconductor integrated circuit chip contained therein to perform shielding inside the semiconductor integrated circuit. Eliminates obstacles caused by induced electric current due to strong electric field including static change of static electricity and discharge.

[0009]

EXAMPLES Specific examples of the semiconductor device according to the present invention will be described below. At present, for example, in order to improve the electrostatic withstand voltage of an IC card, an IC, which has been conventionally arranged in a non-patterned portion of a glass epoxy substrate, is placed on a pattern connected to a power supply voltage V _DD , and then the substrate (substrate) is formed. Attempts have been made to connect the spaces with a conductive adhesive. On the other hand, according to the present invention, even on the IC chip surface side, a ring-shaped conductive material serving as a shield material is directly applied to the periphery to suppress the generation of a potential difference due to a dynamic electric field change or an induced current, and the conduction between the front and back sides of the chip is also taken into consideration for the sleep It tries to miss the charge by.

FIG. 1 is a diagram showing a structure of a semiconductor integrated circuit chip housed in a package of a semiconductor device applied to the above IC card, for example. In FIG. 1, a semiconductor integrated circuit chip (IC chip) 1 is composed of a memory 2, an address counter 3, an oscillator 4, an FET transistor (not shown), and the like. Here, the shield ring 5 made of a conductive material serving as an electrostatic shield material is wound around the entire circuit including the pad portion 6 as well as CR (not shown) that determines the frequency of the oscillator 4. This is because, as shown in FIG. 2, at many points of the IC chip 1, the N ⁺ well 8 in the N ⁻ substrate 7 conducts electricity to make the IC chip equipotential and to function as a short ring. Is to give up.

FIG. 2 shows a CMOS structure in which the entire circuit including the pad portion 6 is surrounded by a shield ring 5 and the inside of the chip is shielded. CMOS above
Is an N-channel (current path) MOS transistor and P
The channel (current path) MOS transistors are connected in series. When the shield ring 5 made of a conductive material that serves as the electrostatic shield material is provided inside the IC chip 1, the power supply voltage terminal V _DD of the pad portion 6 due to the grounding of the external circuit or the power supply impedance.
It is determined which of the power supply voltage terminals V _SS it is advantageous to connect. In the IC chip 1 shown in FIG. 1, the shield ring 5 is connected to the power supply voltage terminal V _DD of the pad section 6.

Here, if the shield ring 5 is connected to the power supply voltage terminal V _SS of the pad portion 6, the portion 9 shown by the broken line in FIG.
It may be replaced with the portion 10 as shown in. In FIG. 3, the shield ring 5 is connected to the power supply voltage terminal V _SS of the pad portion 6 in FIG. At this time, if the P ⁺ well 11 is laid down, the substrate is connected to the power supply voltage terminal V _DD.
If the same electric potential is used, the electron e generated in N ^{− of the} substrate can be applied with an electric field and has an effect of quickly declining. Also, the shield ring 5 and the substrate 5
The depletion layer 12 may be generated in a ring shape by applying a reverse voltage to the. That is, the electric charge e generated in the IC for some reason can be absorbed and reduced at an early stage.

As described above, regardless of whether the shield ring 5 is connected to the power supply voltage terminals V _DD or V _SS of the pad 6, the IC chip 1 applied to the semiconductor device according to the present invention has a pad portion 6 in the periphery of the surface. Since it is surrounded by the shield ring 5 up to the outer side, it is possible to equalize the potential and short-circuit the current due to induction over the entire surface of the IC chip 1.

The semiconductor device according to the present invention not only uses the IC chip having the above-described structure, but also, for example, as shown in FIG. If the technology used is applied, the pad part 1 that needs to be pulled out to the outside on the chip surface
6 may be partially removed and all other parts may be covered with the shield 15. This not only provides stronger protection against electrostatic damage, but also leads to a thinner package in general due to the light blocking effect. Furthermore, it becomes a transmission line (stripline triplet) 17 with a two-layer, three-layer structure, and when applied to an IC card, it seems to be useful for matching in the case of an SP card type in which a microwave antenna is directly led to CMOS and opened and closed. Be done.

Next, a specific example of an IC card to which the semiconductor device having the IC chip shown in FIG. 1 inside is applied and arranged will be described with reference to FIG. FIG. 5 shows the configuration of the entire IC card. In FIG.
The IC element 30 is arranged at a predetermined position on the IC card substrate 22, and is connected to the power supply voltage terminal of the paper battery 28. The IC card substrate 22 is housed in a frame of a frame body 23 formed by punching a sheet material into a frame shape. On the other hand, the sheet member 24 is adhered from the upper surface of the IC card substrate 22 on which components are mounted by a heat-sensitive adhesive material. Next, the sheet member 25 on the side opposite to the component mounting surface of the IC card substrate 22, that is, on the back side of the substrate, is printed with a cautionary note on the use of the IC card 21 on its lower surface, and is a thermosensitive adhesive. To be glued. The sheet members 24 and 25 are made of a high resistance material in order to prevent electrostatic damage, and are coated with a light blocking material in order to prevent light damage.

FIG. 6 shows the IC card substrate 22 located inside the IC card 21. IC card board 22
Is a wiring board 26 with a thickness of 0.1 mm and a reinforcing plate 2 with a thickness of 0.35 mm.
It is formed by stacking 7. The wiring board 26 has an antenna pattern 27a and the like formed on the upper surface. The positive and negative electrodes 28a and 28b are laser-welded to the electrodes for connecting the paper battery 28, and the paper battery 28 is housed in the square hole 27b for housing the paper battery.

In the IC card 21 described above, the structure itself forming the card is provided with a shield effect to prevent a certain amount of electrostatic damage, and further, the IC element 30 arranged at a predetermined position on the IC card substrate 22. By disposing the shield ring 5 also on the surface of the IC chip (IC chip 1 in FIG. 1), the structure can withstand the electrostatic damage that occurs in daily life.

FIG. 7 shows, as the IC card, a CMOS I in which the shield ring 5 is connected to the power supply voltage _VDD side.
It is a circuit diagram when C is applied. In FIG. 7, the shield ring 5 is connected to the power supply voltage V _DD . The output terminal V _OUT is connected to the antenna 31 of the IC card.

At present, as a concrete example of an IC card having a withstand voltage characteristic of about 10 kv / mm, there is one having a structure as shown in FIG. In FIG. 8, an antenna 43, a paper battery 44, and a pattern shape for covering the IC, for example, a silicon resin 45 is provided on the IC card substrate 42. Here, an antistatic shield film piece 46 is a film portion cut out in a local shape including the area where the IC is arranged, that is, a pattern shape that covers at least the IC, for example, a shape including the silicon resin 45. It is made to wrap around from the front side to the back side, and a part of the shield is brought into contact with the pattern of the paper battery 44. That is, as such, an unshielded IC is placed at the position 45 shown in FIG. 8 and, for example, in a wire-bonded IC card, data change or malfunction does not occur due to electrostatic charge or external discharge. As described above, the shield portion 46 is laid over the paper battery portion 44 so as to have the withstand voltage characteristic of about 10 kv / mm.

The semiconductor device according to the present invention has the above I
The application is not limited to the C card, and is also applied to many devices that require semiconductor devices.

[0021]

The semiconductor device according to the present invention has a semiconductor integrated circuit (IC) chip internally formed with a conductive material serving as a ring-shaped electrostatic shield material deposited on the periphery of the surface thereof. , The electrostatic breakdown voltage of the IC itself is improved to prevent electrostatic damage such as data change, malfunction, physical destruction, etc., the operation stop time due to charge-up, so-called sleep time, is shortened, and electromagnetic interference is suppressed, especially when the IC is a compound semiconductor. In some cases, it has excellent moisture resistance. In addition, when the above IC is installed on an IC card, even if it is thin with a thickness of about 1 mm,
The electrostatic breakdown voltage is greatly improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an IC chip arranged in a semiconductor device according to the present invention.

FIG. 2 is a structural diagram of one side of the IC chip shown in FIG.

FIG. 3 is another structural view of the IC chip shown in FIG.

FIG. 4 is a structural diagram of another embodiment of an IC chip arranged in the semiconductor device according to the present invention.

FIG. 5 is a configuration diagram of an IC card to which the semiconductor device according to the present invention is applied.

6 is a configuration diagram of a main part of the IC card shown in FIG.

7 is a circuit diagram of the IC card shown in FIG.

FIG. 8 is another example of an IC card having a shield.

[Explanation of symbols]

 1 IC chip 2 Memory 3 Address counter 4 Oscillator 5 Shield ring 6 Pad area

Claims (1)

[Claims] 1. A semiconductor device having a semiconductor integrated circuit chip inside, wherein a conductive material serving as a ring-shaped electrostatic shield material is adhered and formed on the periphery of the surface of the semiconductor integrated circuit chip.