Patent Description:
Cost, sizes, and electrical characteristics play very important roles in electronic products, and chips (packaged dies), peripheral devices, and printed circuit boards (PCB, Printed Circuit Board) are cores of electronic products. The cost and size of an electronic product greatly depends on the size of a printed circuit board. Additionally, electrical characteristics depend on the length of a wire connecting a chip and a peripheral device and the distance between a filter circuit and a power supply ground, and a device having a smaller physical size has better electrical characteristics. Many of peripheral devices are passive devices such as resistors, inductors, and capacitors. If a die can be directly integrated with these passive devices at a low cost, and the die integrated with the passive devices can then be connected to a printed circuit board through packaging, performance of an electronic product can be improved in terms of cost, size, electrical characteristics, and so on.

A method for integrating a passive device with a die in the prior art is: An under bump metallization (UBM, Under Bump Metallization) layer is disposed on a die, a solderable bump is formed on the under bump metallization layer through printing or electroplating, and integration of the die with a passive device is then implemented. In this method, a UBM layer needs to be formed additionally, which results in an additional cost. The prior art further provides a method for integrating a passive device with a die, in which a passive device is directly bonded to a die by using an electrically conductive adhesive. However, during process implementation of this method, residues of adhesive impurities occur easily, which affects a yield of semiconductor packaging. In addition, compared with metal, a conductive adhesive has poor conductivity, which affects electrical characteristics of integrated passive devices.

<CIT> discloses a method of connecting a chip with a substrate by means of bump connectors, which are formed by stud bumping and are then coated with an organic protective layer.

Also <CIT> discloses a method of connecting a chip with a substrate with bump connectors: the bump connectors are formed by stud bumping using a metal wire coated with palladium or the like.

A chip integration method is provided, so that integration becomes easy and costs are low. The present disclosure has been defined in the independent claim <NUM>. Further technical features have been defined in the dependent claims.

In the chip integration method of the present invention, no UBM layer needs to be formed in an additional process step, and therefore, integration becomes easy and costs are low. In the present invention, a die bonding portion of a die and a passive device bonding portion of a passive device are disposed opposite to each other and are connected through a connecting piece. In this way, a path connecting the die to the passive device of the chip integration module and the chip package structure becomes shorter, and overall sizes of the chip integration module and the chip package structure are reduced.

To describe the technical solutions in the embodiments of the present invention or in the prior art more clearly, the following briefly introduces the accompanying drawings required for describing the embodiments or the prior art.

The following clearly and completely describes the technical solutions in the embodiments of the present invention as defined by the appended claims and with reference to the accompanying drawings in the embodiments of the present invention.

Referring to <FIG>, a first example not forming part of the present invention provides a chip integration module <NUM>, including a die <NUM>, a passive device <NUM>, and a connecting piece <NUM>, where the die <NUM> and the passive device <NUM> are connected to each other through the connecting piece <NUM>.

In this example, a logical circuit, a storage device, or another type of circuit may be used as the die <NUM>, and a semiconductor component such as a diode, a transistor, or a capacitor may further be disposed on the die <NUM>. The die <NUM> is provided with at least one die bonding portion <NUM>. As shown in the figures, in this embodiment, two die bonding portions <NUM> are provided, and the die bonding portions <NUM> are formed on the die <NUM> and are exposed from the die <NUM>.

The die bonding portion <NUM> is made of sheet-like metal, and preferably, the die bonding portion <NUM> is made of aluminum (Al), copper (Cu), or an alloy of aluminum and copper. It may be understood that the die bonding portion <NUM> may be directly formed on the die <NUM>, and the die bonding portion <NUM> may also be connected to the original die <NUM> in various manners on the basis of the original die <NUM>, so as to form the die <NUM> provided with the die bonding portion <NUM>. For example, the die bonding portion <NUM> may be formed on the surface of the die <NUM> by means of sputtering (sputtering), chemical vapor deposition (CVD, Chemical Vapor Deposition), or the like, and a specific forming manner of the die bonding portion <NUM> is not described herein in detail.

An integrated passive device (IPD, Integrated Passive Devices) or a discrete passive device, for example, a filter or various types of capacitors such as a normal capacitor or a multi-layer ceramic capacitor (MLCC, Multi-Layer Ceramic Capacitor) may be used as the passive device <NUM>. The passive device <NUM> is provided with a passive device bonding portion <NUM> that corresponds to each die bonding portion <NUM> of the die <NUM>. As shown in <FIG>, in this example, two passive device bonding portions <NUM> are provided likewise. The passive device bonding portions <NUM> are formed on the passive device and are exposed from the passive device <NUM>. The passive device bonding portion <NUM> is made of sheet-like metal; and preferably, the passive device bonding portion <NUM> is made of aluminum (Al), copper (Cu), or an alloy of aluminum and copper. Similarly, the passive device bonding portion <NUM> may be formed on the surface of the passive device <NUM> by means of electroplating, sputtering (sputtering), chemical vapor deposition (CVD, Chemical Vapor Deposition), or the like, and a specific forming manner of the passive device bonding portion <NUM> is not described herein in detail.

The connecting piece <NUM> is block-shaped. The die bonding portion <NUM> of the die <NUM> and the passive device bonding portion <NUM> of the passive device <NUM> are disposed opposite. The connecting piece <NUM> is connected to the die bonding portion <NUM> of the die <NUM> and the passive device bonding portion <NUM> of the passive device <NUM>, and the connecting piece <NUM> is located between the die bonding portion <NUM> of the die <NUM> and the passive device bonding portion of the passive device <NUM> to connect the die <NUM> to the passive device <NUM>. In this example, the connecting piece <NUM> may be made of any one of gold (Au), silver (Ag), copper (Cu), titanium (Ti), nickel (Ni), and aluminum (Al), or an alloy formed of any two or more of the metal. It may be understood that solder may further be added to constituents of the connecting piece <NUM>, so that the connecting piece <NUM> is easily connected to the die <NUM> and the passive device <NUM> by means of welding.

Further, in this example, as shown in <FIG>, the die <NUM> is provided with a die surface <NUM>, the die bonding portion <NUM> is provided with a die bonding surface <NUM>, and the die bonding surface <NUM> is concave or convex with respect to the die surface <NUM>, or flush with the die surface <NUM>.

Similarly, the passive device <NUM> is provided with a passive device surface <NUM>, the passive device bonding portion <NUM> is provided with a passive device bonding surface <NUM>, and the passive device bonding surface <NUM> is concave or convex with respect to the passive device surface <NUM>, or flush with the passive device surface <NUM>.

It may be understood that the die bonding portion <NUM> and the passive device bonding portion <NUM> may be disposed or formed on the die <NUM> and the passive device <NUM> in any applicable manner, as long as it is ensured that the die bonding portion <NUM> and the passive device bonding portion <NUM> can be exposed from the die <NUM> or the passive device <NUM>, so that the die bonding portion <NUM> and the passive device bonding portion <NUM> are connected to the connecting piece <NUM>.

In an assembled state, the die bonding portion <NUM> of the die <NUM> and the passive device bonding portion <NUM> of the passive device <NUM> are disposed opposite to each other, and are connected to each other through the connecting piece <NUM>, so that the passive device <NUM> is connected to the die <NUM> in an integrated manner. It may be understood that disposition positions and quantities of the die bonding portions <NUM> of the die <NUM>, the passive device bonding portions <NUM> of the passive device <NUM>, and the correspondingly disposed connecting pieces <NUM> may be set according to use and connection requirements.

As shown in <FIG>, a chip integration method of the chip integration module <NUM> in this example (which does not define the present invention, but is useful for illustrating some of its aspects) includes the following steps:.

Step S2 further includes the following steps:
Step S21: Form the connecting piece <NUM> on one of the die bonding portion <NUM> and the passive device bonding portion <NUM>. In this embodiment, the connecting piece <NUM> may be formed on the die bonding portion <NUM> of the die <NUM>. Specifically, in step S21, the weldable connecting piece <NUM> may be formed on the die bonding portion <NUM> on the surface of the die <NUM> by means of wire bonding and cutting.

As shown in <FIG>, when the weldable connecting piece <NUM> is formed on the die bonding portion <NUM> on the surface of the die <NUM> by means of wire bonding and cutting, the die <NUM> is first fixed by using a vacuum nozzle <NUM> of a wire bonder. A wire <NUM> is then selected, the wire <NUM> is threaded through a welding joint <NUM> of the wire bonder, and a wire ball <NUM> is formed at an end of the wire <NUM> by using the welding joint <NUM>. The welding joint <NUM> of the wire bonder is moved, so that the wire ball <NUM> contacts the die bonding portion <NUM> on the surface of the die <NUM>. The wire ball <NUM> is bonded with the die bonding portion <NUM> on the surface of the die <NUM> by using the welding joint <NUM> of the wire bonder, where the die <NUM> may be preheated before the wire ball <NUM> is bonded. The wire <NUM> is cut, and the wire ball <NUM> stays on the die bonding portion <NUM> of the die <NUM> as the connecting piece <NUM>.

It may be understood that in the chip integration method in this example, the connecting piece <NUM> may also be first formed on the passive device bonding portion <NUM> of the passive device <NUM> by means of wire bonding and cutting, and specific steps of forming are similar to the foregoing steps and are not described herein in detail. A material of the wire <NUM> is consistent with a material of the eventually formed connecting piece <NUM>.

Step S22: Connect the connecting piece <NUM> to the other of the die bonding portion <NUM> and the passive device bonding portion <NUM>.

Further, in the chip integration method in this example, the connecting piece <NUM> connected to the die bonding portion <NUM> may also be connected to the passive device bonding portion <NUM> of the passive device <NUM> by using any applicable method.

As shown in <FIG>, specifically, in this example, after the connecting piece <NUM> is formed on the die bonding portion <NUM> of the die <NUM> in step S21, the connecting piece <NUM> may further be connected to the passive device by means of ultrasonic welding and thermocompression bonding, so as to implement integration of the die <NUM> and the passive device <NUM>.

Specifically, the passive device <NUM> is fixed by using the vacuum nozzle <NUM>. The passive device <NUM> enables the connecting piece <NUM> connected to the die <NUM> to contact the passive device bonding portion <NUM> of the passive device <NUM>, and pressure and ultrasonic friction are applied on the connecting piece <NUM> by using a welding joint of an ultrasonic welding machine, so that the connecting piece <NUM> and the passive device <NUM> are connected to each other by means of thermocompression bonding and ultrasonic welding. It may be understood that in the chip integration method in this example, the connecting piece <NUM> may also be connected to the die <NUM> and the passive device <NUM> by using any other applicable method. It may be understood that in a process of connecting the connecting piece <NUM> to the die <NUM> and the passive device <NUM>, the connecting piece <NUM> may deform to some extent, and the connecting piece <NUM> may have a shape after a deformation of any form.

<FIG> shows a chip integration module <NUM> of a first exemplary embodiment of the present invention. The chip integration module <NUM> in this embodiment is approximately the same as the chip integration module <NUM> in the first example. The chip integration module <NUM> includes a die <NUM>, a passive device <NUM>, and a connecting piece <NUM>, where the die <NUM> is provided with a die bonding portion <NUM>, the passive device <NUM> is provided with a passive device bonding portion <NUM>, and the die bonding portion <NUM> of the die <NUM> and the passive device bonding portion <NUM> of the passive device <NUM> are disposed opposite to each other and are connected to each other through the connecting piece <NUM>.

A difference lies in that a protective layer <NUM> is provided on the surface of the connecting piece <NUM>, and the protective layer <NUM> at least covers a part of the surface of the connecting piece <NUM>. An organic solderability preservative (OSP) layer <NUM> is used as the protective layer <NUM>. Some aspects of the chip integration method of the chip integration module <NUM> in this embodiment are similar to those in the first example and are not described herein in detail.

According to the invention, the protective layer <NUM> is formed by using a wire having a protective layer, that is, the connecting piece <NUM> is formed on the die bonding portion <NUM> on the surface of the die <NUM> by means of wire bonding and cutting a wire with the protective layer <NUM> and in this way, the formed connecting piece <NUM> also has the protective layer <NUM>.

Further, a gap is provided between the die <NUM> and the passive device <NUM>, and the gap between the die <NUM> and the passive device <NUM> is filled with a filling material <NUM>, where an underfill (underfill) or another filling material may be used as the filling material <NUM>.

<FIG> shows a chip integration module <NUM> of a second exemplary embodiment of the present invention. The chip integration module <NUM> in this embodiment is approximately the same as the chip integration module <NUM> in the first exemplary embodiment.

In this embodiment, the chip integration module <NUM> includes a die <NUM>, a passive device <NUM>, and a connecting piece <NUM>, where the die <NUM> is provided with a die bonding portion <NUM>, the passive device <NUM> is provided with a passive device bonding portion <NUM>, and the die bonding portion <NUM> of the die <NUM> and the passive device bonding portion <NUM> of the passive device <NUM> are disposed opposite to each other and are connected to each other through the connecting piece <NUM>.

A difference lies in that the connecting piece <NUM> in this embodiment includes a first connecting piece <NUM> and a second connecting piece <NUM>, where the first connecting piece <NUM> is connected to the die bonding portion <NUM> of the die <NUM>, the second connecting piece <NUM> is connected to the passive device bonding portion <NUM> of the passive device <NUM>, and the first connecting piece <NUM> and the second connecting piece <NUM> are connected to each other, so that the passive device <NUM> is connected to and is integrated with the die <NUM>.

It may be understood that, same as that for the chip integration module <NUM> in the first example, the passive device <NUM> and the die <NUM> may be correspondingly disposed with multiple passive device bonding portions <NUM> and multiple die bonding portions <NUM>, and multiple pairs of first connecting pieces <NUM> and second connecting pieces <NUM> that correspond to the multiple passive device bonding portions <NUM> and the multiple die bonding portions <NUM> may be disposed on the chip integration module <NUM>. Materials of the first connecting piece <NUM> and the second connecting piece <NUM> are the same as the material of the connecting piece <NUM> in the first example.

Even if this is not shown in <FIG>, according to the invention the protective layer <NUM> in the first embodiment also partially covers the first connecting piece <NUM> and the second connecting piece <NUM> of the connecting piece <NUM> in this embodiment. A gap between the die <NUM> and the passive device <NUM> may also be filled with a filling material <NUM>. Some aspects of the chip integration method of the chip integration module <NUM> in this embodiment are similar to those of the chip integration method in the first example and this chip integration method comprises the following steps:.

A difference lies in that in this embodiment, step S2 further includes the following steps:.

In this embodiment, manners of connecting the connecting piece <NUM> to the die <NUM> and the passive device <NUM> are consistent.

<FIG> shows a chip package structure <NUM> according to an example not forming part of the present invention. The chip package structure includes a base <NUM> and a die integration module <NUM> disposed on the base. The die integration module <NUM> has a structure that is approximately the same as the die integration module described in the first example or the first exemplary embodiment of the invention, and includes a die <NUM>, a passive device <NUM>, and a connecting piece <NUM>, where the die <NUM> is provided with a die bonding portion <NUM>, the passive device <NUM> is provided with a passive device bonding portion <NUM>, and the die bonding portion <NUM> of the die <NUM> and the passive device bonding portion <NUM> of the passive device <NUM> are disposed opposite to each other and are connected to each other through the connecting piece <NUM>.

A connection wire <NUM> is further provided on the chip package structure <NUM>, the die <NUM> of the die integration module <NUM> is further provided with a connection wire bonding portion, and the connection wire is connected between the connection wire bonding portion and the base <NUM> to connect the die <NUM> to the base <NUM> by means of wire bonding.

In this example, a lead-frame (lead-frame), a substrate (substrate), or a semiconductor material such as a semiconductor wafer may be used as the base <NUM>. A moulding compound <NUM> for protecting the die integration module <NUM> may further be formed on the base <NUM>. It may be understood that the die integration module <NUM> may be disposed on the base by using any applicable prior art. For example, a connection wire may be canceled from the chip package structure <NUM>, and the die <NUM> of the die integration module <NUM> is connected to the base <NUM> by means of flip-chip bonding.

Claim 1:
A chip integration method, comprising the following steps:
providing a die (<NUM>; <NUM>) and a passive device (<NUM>; <NUM>), wherein the die is provided with a die bonding portion (<NUM>; <NUM>),
and the passive device is provided with a passive device bonding portion (<NUM>; <NUM>); and disposing a connecting piece (<NUM>; <NUM>), wherein the connecting piece (<NUM>; <NUM>) is connected to the die bonding portion (<NUM>; <NUM>) and the passive device bonding portion (<NUM>; <NUM>), and the connecting piece (<NUM>; <NUM>) is located between the die bonding portion (<NUM>; <NUM>) and the passive device bonding portion (<NUM>; <NUM>);
wherein no under bump metallization, UBM, layer is formed in an additional process step;
wherein the connecting piece (<NUM>; <NUM>) is formed on at least one of the die bonding portion (<NUM>; <NUM>) and the passive device bonding portion (<NUM>; <NUM>) by means of wire bonding and cutting
wherein a protective layer (<NUM>) is provided on the surface of the connecting piece (<NUM>; <NUM>), and the protective layer (<NUM>) at least covers a part of the surface of the connecting piece (<NUM>; <NUM>),
wherein the protective layer (<NUM>) is made of an organic solderability preservative; characterised in that the protective layer (<NUM>) is formed by using a wire having the protective layer for forming the connecting piece (<NUM>; <NUM>) on to at least one of the die bonding portion (<NUM>; <NUM>) and the passive device bonding portion (<NUM>; <NUM>) by means of wire bonding and cutting