KR20010015552A - Igniter - Google Patents

Abstract

The present invention relates to an igniter, in particular an igniter for triggering the passenger protection means of a motor vehicle, in which an integrated circuit device 21 for controlling the occupying element 31 in such an igniter is configured as a semiconductor chip 2, and An integrated capacitor 1 for supplying energy for the process is constructed as an additional semiconductor chip 1. The two semiconductor chips 1 and 2 are placed on top of each other in a capsule of an igniter containing ignition powder. This makes it possible to maintain the size of a conventional igniter.

Description

Igniter {IGNITER}

The known igniter WO 96 / 12926-A includes a metal carrier with a cap on top. The cap and the carrier form a capsule filled with ignition material. The first coupling pin is attached to the metal carrier, and the additional coupling pin passes through the carrier in an insulating manner and protrudes into the capsule. On the side of the carrier facing the ignition material, a semiconductor ignition element is disposed which is conductively coupled to the further coupling pin by a bonding wire.

In EP 0 471 871 A1 a passenger protection system for a vehicle is known, which is coupled to various protection means of a vehicle via a data line and has a control located centrally in the vehicle. In this arrangement, each protection means is in particular assigned to an electrical circuit which receives and decodes the ignition command transmitted from the central control unit. In addition, an energy storage capacitor is located in each passenger protection means such that, in response to a control signal from the control device, the electrical circuitry causes the energy stored in the capacitor to be transferred to the ignition element of the passenger protection means, thereby triggering the passenger protection means. do.

It is an object of the present invention to provide a space-saving device of an electrical circuit associated with passenger protection means, which circuit is coupled to a central control device via a data line.

According to the invention, this object is achieved by the features of claim 1.

In such a device, the electrical circuit and the energy storage capacitor are for example embedded / integrated in an igniter known from WO 96 / 12926-A. Since the igniter according to the present invention does not differ in shape and size from known igniters, the electrical circuit is constructed as an integrated circuit device on a semiconductor substrate and allows a minimum size due to integration. Furthermore, the capacitors provided for energizing the ignition process are also constructed as integrated components having other semiconductor chip types. In such a device, a first semiconductor chip comprising a capacitor is arranged with a wide side facing the wide side of the second semiconductor chip comprising the integrated circuit, such that the semiconductor chips are stacked on top of each other as a so-called package, This ensures that the minimum space is used when integrated. Such a package is preferably located on the metal carrier of the igniter, which forms at least the capsule together with the ignition material afterwards. The two broad sides of the semiconductor chip each have a much larger area than one of the four end faces in the tubular chip.

Since the circuit arrangement and the capacitor are configured as integrated parts in accordance with the invention and these parts are stacked in accordance with the invention, all the components necessary for the passenger protection system according to EP 0 471 871 A1 are located spatially adjacent to the passenger protection means and normally Phosphorus can be accommodated in the igniter. As a result, it becomes apparent to have several advantages: As far as the igniter is concerned, only a single plug-in coupling between the igniter and the data line provided as part of the cable tree is required. In contrast, a detachable adapter for receiving electrical circuits between the cable tree and the igniter has two plug-in couplings, one coupled to the cable tree and the other to the conventional igniter. Thus, by using the igniter according to the present invention, the risk of improper contact and temporary polarity inversion is minimized.

Such an igniter, which is provided for triggering the passenger protection means, is generally plugged into the housing of the gas generator or mechanically coupled. The gas generator also has a break joint or opening facing the folded air bag. The ignition material of the igniter explodes as the ignition element in the igniter heats up, resulting in sufficient energy being transferred to the gas generator, causing the gas tablet to exit the gas into the airbag. The gas generator generally has a mounting point or opening for receiving a conventional igniter with a predetermined geometry. Next, according to the present invention, if the entire electronic components including the capacitors are integrated into a conventional igniter without a change in structural shape and size, a conventional gas generator can be used with the igniter according to the present invention, on the one hand No structural changes are necessary and, on the other hand, the necessary parts of the igniter also do not change in structural design compared to conventional igniters. For example, a metal carrier such as a cap can have the same structural design as a known igniter.

In addition, the igniter according to the invention requires only minimal parts and is simply manufactured.

To construct a capacitor as an integrated component that can accommodate enough energy to ignite the passenger protection means, see the paper entitled "New Capacitor Technology Based on Porous Silicon" by Lehmann et al. Thin Solid Films. In this paper, a number of holes are etched vertically into the silicon substrate. The deposited dielectric layer and the polysilicon layer deposited on the dielectric layer form a capacitor with the substrate, and the substrate and the polysilicon layer form a wide-area capacitor plate due to the many holes. In order to construct and manufacture such capacitors, reference is made to the aforementioned technical documents, which are incorporated herein by reference.

Preferred variations of the invention are disclosed in the dependent claims.

Embodiments and modifications of the present invention will be described in detail with reference to the drawings.

The invention relates to the igniter claimed in the preamble of claim 1.

1 is an electrical circuit diagram of an igniter.

2 is a view from above of an assembly view of an igniter according to the invention;

Figure 3 is a view of the assembly of the igniter according to the present invention from below.

1 shows an electrical circuit diagram of an igniter according to the invention. In order to couple the igniter to the coupler of the cable tree, a coupling part 6 is provided on the side of the igniter, which is coupled to the integrated circuit device 21 via one decoupling resistor 61 and filter capacitor 62, respectively. In addition, an ignition element 31 and a storage capacitor 11 in the form of a heating resistor are coupled to the integrated circuit device 21.

In the following description, the operation of the individual components will be described in detail: since at least two couplings 6 are coupled to the data bus on the side of the cable tree, for example, the short circuit in the integrated circuit device 21 is entirely integrated. The bus system may malfunction. To protect the bus from this short circuit, a high-impedance decoupling resistor 61 is provided in each coupling path. Filter capacitor 62 is used to filter out interfering high-frequency electromagnetic radiation. The capacitor 11 is used to provide an appropriate amount of energy to ignite or trigger the corresponding passenger protection means. The ignition element 31 is configured as a resistance heating wire that is thermally coupled to an ignition material, for example an ignition powder. The integrated circuit device 21 receives a message transmitted through the coupling part 6 from the central control unit of the passenger protection means. Such a message may include triggering information or diagnostic information. To this end, the integrated circuit device incorporates an interface suitable for evaluating the data bus and received data, for allowing transmitted messages to be emitted and for coupling to a control unit in the form of a microprocessor for performing control and test routines. Have When the integrated circuit device detects the delivered ignition command, it in turn activates the integrated electrically controllable switch by the energy stored in the energy storage capacitor 11 being transferred to the ignition element 31 in the form of a heating current.

2 is a view from above of an assembly view of an igniter according to the invention; The igniter according to the invention comprises three joining pins 6 which pass through the plastic holder 7 in the opening of the metal carrier 5 with the glass insulator 51. The metal carrier 5 is used as a carrier element for three planar semiconductor chips 1, 2, 3. The first semiconductor chip 1 has an integrated capacitor, the second semiconductor chip 2 has an integrated circuit device, and the third semiconductor chip 3 has an ignition element. According to FIG. 2, the second and third semiconductor chips 2, 3 each have a contact region 4 on their wide side, the contact region 4 of the second semiconductor chip 2 being the second semiconductor. Disposed on the protruding region of the chip 2, the contact between the third semiconductor chip 3 and the second semiconductor chip 2 via the bonding wire 41 when the semiconductor chips 2, 1, 3 are stacked; Be sure to The first semiconductor chip 1 is preferably coupled to the second semiconductor chip 2 in so-called "flip chip technology". To this end, the two semiconductor chips 1, 2 have contact regions 4 which are not shown on a wide face facing each other, which contact regions face each other when the two semiconductor chips are stacked on each other, An electrical contact is formed between the chips 1, 2.

The individual semiconductor chips are preferably interconnected via an adhesion layer. If desired, additional insulating layers are required between the individual semiconductor chips to prevent short circuits between the semiconductor chips representing the individual elements and to make electrical contact only in a defined manner through their contact areas.

The third semiconductor chip is preferably a silicon substrate, on which a polysilicon layer having a thin cross-sectional area is deposited. This thin cross-sectional area is used as heating resistance when current flows through it. However, the heating resistance may be integrated into the first semiconductor chip. To this end, the first semiconductor chip does not have the above-described holes but includes a region in which a polysilicon layer is deposited to form one of the capacitor electrodes. In this substrate region, the polysilicon layer is constructed with a thin cross section in the region defined such that this region of the polysilicon layer forms a resistive heating element. Therefore, with this configuration of the ignition element, the third semiconductor chip can be omitted.

As an alternative to the above-described configuration of the ignition element, the second semiconductor chip may comprise the ignition element. To this end, the polysilicon layer region used as the contact layer for the electrical circuit is etched freely and used as a resistive heating element within this exposed region.

It should be noted that in all elements of the ignition element, the ignition element has a good thermal coupling with the ignition material. For this reason, the semiconductor chip containing the resistive element is preferably arranged on top. The bottom semiconductor chip is preferably coupled to the metal carrier 5 via an attachment joint. The metal carrier 5 is used on the one hand as a heat sink for the integrated circuit device. In addition, it is used as a mechanical stabilizing element for an igniter. The metal carrier can also be used as a protective shield against severe mechanical reactions on the data bus itself in the event of explosion of a ignition material or plug-in coupling to the data bus.

It can be seen from FIG. 3 that in each case the coupling pin 6 has a decoupling resistor 61. The filter capacitor 62 is located between the two coupling pins 6. The engagement pin 6 and the components 61, 62 are fixed in place by a plastic holder.

In the following the advantages of the manufacturing method according to the invention are disclosed: The joining pin 6 is part of a pressed screen stamped from a metal sheet. After stamping, the components 61, 62 are provided on the pressed screen. Next, the plastic holder 7 is molded in the pressed screen. Next, the extra electrical couplings used for the mechanical stability of the pressed screen during the mounting of the components between the coupling pins are punched out. The device with the plastic holder 7 and the coupling pin 6 formed in this position is then coupled to the metal carrier 5, where the coupling pin 6 is pressed into the glass insulator 51 of the metal carrier 5. do. During these processes. The semiconductor chip is preferably mounted in advance on the metal carrier in a stacked manner. For this purpose, the individual semiconductor chips are each bonded to each other and to the metal carrier. When flip chip technology is used, the individual semiconductor chips are already in contact with each other. Otherwise, the winding contacts between the semiconductor chips where required and the bonding contacts between the coupling pins and the contact regions of the integrated circuit device are formed after the metal carrier is bonded to the semiconductor chip and the plastic holder 7.

Next, the cap 8 is placed on the metal carrier 8 and firmly joined, for example, by flanging. In this arrangement, the cap 8 has an opening at its front end, through which the ignition material is filled and pressed into the capsule formed by the cap 8 and in particular the metal body 5. Thus, the ignition material then surrounds the semiconductor chips 1 to 3. In the following, the cap is hermetically welded to the lid although not shown.

Claims (12)

In the igniter for passenger protection means for automobiles, An ignition element 31 which reacts with the ignition material, A first semiconductor chip (1) having a capacitor (11) for supplying energy for ignition and configured as an integral part, A second semiconductor chip 2 having an integrated circuit device 21 for controlling the ignition element 31, The first semiconductor chip (1) has a wide side facing the wide side of the second semiconductor chip (2). The igniter according to claim 1, wherein the first and second semiconductor chips (1, 2) are arranged on top of each other. The igniter according to claim 1 or 2, characterized in that the ignition element (31) is configured as a resistance heating wire. 4. A third semiconductor chip (3) comprising the ignition element (31), wherein the third semiconductor chip (3) comprises the first and second semiconductor chips (1). And a wide face facing the wide face of 2). 5. An igniter according to claim 4, wherein the third semiconductor chip (3) is located on the first semiconductor chip (1). The igniter according to one of the preceding claims, characterized in that each semiconductor chip (1, 2, 3) has a contact area (4) for electrical contact. The igniter according to claim 6, wherein the contact areas (4) of the first and second semiconductor chips (1, 2) are mutually coupled via a bonding wire (41). 8. An igniter according to claim 7, wherein the second semiconductor chip (2) region is at least as large as the contact region (4) than the first semiconductor chip (1) region. 7. Igniter according to claim 6, characterized in that the respective contact areas (4) are located on the wide face of each semiconductor chip (1, 2, 3). The igniter according to claim 6, wherein the contact areas (4) of the first and second semiconductor chips (1, 2) are located directly on top of each other. The at least one metal carrier 5 and the cap 8 located on the metal carrier 5 form a capsule for the ignition material and the semiconductor chip according to claim 1. (1, 2, 3) are located on top of each other on the metal carrier (5). 12. The igniter according to claim 11, characterized in that the coupling pin (6) for the integrated circuit (21) passes through the metal carrier (5) in an insulating manner.