TWI538588B - Production method for airtight via of a substrate - Google Patents

Description

Method for manufacturing gas tight metal guide hole

The invention relates to a method for manufacturing a metal via hole, in particular to a method for manufacturing a gas tight metal via hole.

Almost all electronic products and their applications must use more than one substrate to carry components, route electronic circuits, and form the necessary device connections. As for the partial analysis of the electronic circuit, since the surface area of the substrate needs to be fully used, the electronic circuit is generally disposed using the multi-layer board, and thus the connection of the electronic circuits between the layers of the substrate becomes more complicated and more important.

In the process of all substrates, the connection of the electronic circuits between the layers of the substrate is usually formed by mechanical drilling or laser drilling, and the metal holes are filled in the guiding holes to electrically conduct the two ends of the guiding holes. The electronic circuitry of the substrate is then separately connected to the vias to form a complete circuit over the entire substrate.

However, due to the temperature shrinkage characteristics of the metal substance, the metal material in the via hole often has voids inside and cannot be hermetically sealed. Then, when the substrate is used in a vacuum packaging process, there is A leak problem arises. Therefore, when using a multi-layered substrate, it is usually necessary to connect the wires up and down. Displacement between layers is used to avoid leakage problems during direct penetration. However, this method must be fabricated on the green substrate, and it is completely unusable for the sintered mature substrate.

In view of this, how to develop a method for creating a completely airtight guide hole can be applied not only to the guide hole of the green substrate but also to the production of the airtight guide hole on the cooked mature substrate. An important topic in the contemporary electronics industry.

The invention relates to a method for manufacturing a gas-tight metal via hole, which comprises the following steps of sequentially: providing a substrate; forming a metal via hole; performing hole filling; performing liquid pressure equalization; performing first sintering; printing gas a dense metal paste; a printed wire; and a second sintering. Through the implementation of the invention, the metal via hole of the substrate can be ensured to be airtight without causing leakage in the packaging process, thereby effectively improving the reliability of the substrate and the application product thereof.

The invention provides a method for manufacturing a gas-tight metal via hole, comprising the steps of: providing a substrate, wherein the substrate has a first surface and a second surface opposite to the first surface; forming a metal guide a hole, which is formed by a plurality of metal vias penetrating through the substrate and penetrating the first surface and the second surface; filling the holes, filling each metal via hole with a metal paste; performing liquid pressure equalization densification, The substrate is vacuum-coated with a coating film, and the coated substrate is uniformly densified by liquid pressure at a specific pressure with a liquid fluid, and then the coating is removed; the first sintering is performed. The method is characterized in that the substrate is sintered to cure the metal paste in the metal via holes; and the airtight metal paste is printed on the metal via hole and the first surface and the second surface are printed and fixed with a gas-tight metal paste. , airtight metal paste and metal The paste is bonded and electrically connected; the printed wire is printed on the first surface or the second surface and fixed with at least one wire, and the wire is electrically connected to the airtight metal paste and electrically connected to the at least one metal via hole A common circuit is formed; and a second sintering is performed, which is performed by sintering the substrate to cure the hermetic metal paste and the wire.

With the implementation of the present invention, at least the following advancements can be achieved:

First, ensure that the metal via holes of the substrate are airtight without causing leakage in the packaging process.

Second, it can be applied to the raw germ substrate before sintering and the mature embryo substrate after sintering.

Third, the production cost is low, and it is not necessary to use expensive machinery and equipment.

Fourth, effectively improve the reliability of the substrate and its application products.

In order to make those skilled in the art understand the technical content of the present invention and implement it, and according to the disclosure, the patent scope and the drawings, the related objects and advantages of the present invention can be easily understood by those skilled in the art. Therefore, the detailed features and advantages of the present invention will be described in detail in the embodiments.

10‧‧‧Substrate

11‧‧‧ first surface

12‧‧‧ second surface

20‧‧‧Metal Guide Hole

30‧‧‧metal paste

40‧‧‧Steel

50‧‧‧The direction of vacuum attraction

60‧‧‧ envelope

70‧‧‧Special pressure

80‧‧‧Airtight metal paste

85‧‧‧Web Edition

86‧‧‧ scraper

90‧‧‧ wire

S100‧‧‧Method for manufacturing airtight metal guide holes

S10‧‧‧ provides a substrate

S20‧‧‧ forming metal guide holes

S30‧‧‧ fill holes

S40‧‧‧ Liquid pressure equalization

S50‧‧‧First sintering

S60‧‧‧Printing airtight metal paste

S70‧‧‧Printed wire

S80‧‧‧Second sintering

FIG. 1 is a flow chart showing the steps of a method for manufacturing a gas-tight metal via hole according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a substrate and a metal via hole according to an embodiment of the present invention.

FIG. 3A is a cross-sectional view showing a substrate in which a metal via hole is formed and a metal paste is filled in the metal via hole according to an embodiment of the present invention.

FIG. 3B is a schematic cross-sectional view showing a metal plate filled with a metal paste by a steel plate and vacuum suction according to an embodiment of the present invention.

Figure 4 is a schematic view showing a step of performing liquid pressure equalization densification according to an embodiment of the present invention Figure.

FIG. 5A is a cross-sectional view showing a gas-tight metal paste adhered to a metal via hole at a first surface and a second surface according to an embodiment of the present invention.

FIG. 5B is a schematic view showing a method of printing and fixing a gas-tight metal paste on a metal guide hole at a position where the metal guide hole is in contact with the first surface and the second surface by a screen printing method according to an embodiment of the invention.

Figure 6 is a schematic view showing a metal via hole, a metal paste, a gas-tight metal paste, and a wire connected to each other according to an embodiment of the present invention.

【Method of implementation】

As shown in FIG. 1 , the present embodiment is a method for manufacturing a gas-tight metal via hole, which includes the following steps: providing a substrate (step S10); forming a metal via hole (step S20); Filling the hole (step S30); performing liquid pressure equalization (step S40); performing the first sintering (step S50); printing the airtight metal paste (step S60); printing the wire (step S70); and performing the second time Sintering (step S80).

As shown in FIG. 1 and FIG. 2, a substrate is provided (step S10), which uses a substrate 10 as a base for manufacturing a gas-tight metal via 20, wherein the substrate 10 has a first surface 11 and a first Surface 11 is opposite one of the second surfaces 12. The substrate 10 used may be a ceramic substrate having characteristics and advantages of being strong, resistant to high temperatures, and not easily deformed.

As shown in FIGS. 1 and 2, a metal via hole is formed (step S20), and a plurality of metal via holes 20 that penetrate the first surface 11 and the second surface 12 are formed on the substrate 10. The metal via 20 can be formed by laser drilling, mechanical drilling or high pressure liquid drilling.

As shown in Fig. 1 and Fig. 3A, a hole is filled (step S30), which is It is filled with a metal paste 30 and fills each of the metal via holes 20. The metal paste 30 may be formed of an alloy material of silver, copper, gold, platinum, palladium or at least two of the above materials.

As shown in FIG. 1 , FIG. 3A and FIG. 3B , when the step of filling the hole (step S30 ) is performed, the stencil 40 may be covered on the first surface 11 and the vacuum may be applied to the second surface 12 . attract. As shown in FIG. 3B, the direction 50 of vacuum suction is the direction opposite to the side on which one side of the metal paste 30 is filled with the metal via 30, and is separated from the substrate 10.

The steel plate 40 used for the step of filling the holes (step S30) has a plurality of holes 41 completely corresponding to the metal guide holes 20, so that the metal paste 30 can be easily guided into each of the metal guide holes 20. Within, each metal via 20 is completely filled.

In order to control the cost, the size of the steel plate 40 used can be made to be comparable to the size of the substrate 10, and the thickness of the steel plate 40 can reach a thickness that does not bend or damage the steel plate 40 when it is used. Just fine.

As shown in FIGS. 1 and 4, liquid pressure equalization is performed (step S40), which is a substrate in which the coating film 60 is vacuum-coated on the substrate 10 and the coating film 60 is coated with a liquid fluid. 10 is uniformly subjected to liquid pressure equalization at a specific pressure 70 (step S40), and then the envelope 60 is further removed.

The material to be used for the envelope 60 is not particularly limited, and may be selected from materials which do not break in the step of performing liquid pressure equalization (step S40) or which do not physically or chemically react with the metal paste 30.

On the other hand, in the step of performing liquid pressure equalization (step S40), the specific pressure 70 applied by the liquid fluid may be a pressure of 100 psi or more. Thus, sufficient pressure can be applied to uniformly densify the metal paste 30 filled in the metal via 20 .

As shown in Fig. 1, a first sintering (step S50) is performed to sinter the substrate 10 to cure the metal paste 30 in the metal vias 20. The temperature profile used in the step of performing the first sintering (step S50) is not particularly limited, and a temperature profile in which only the metal paste 30 in the metal via 20 is completely cured can be applied.

As shown in FIG. 1 and FIG. 5A, a gas-tight metal paste is printed (step S60), and a metal-tight metal paste is printed and fixed at a position where each metal via 20 is in contact with the first surface 11 and the second surface 12. 80. The airtight metal paste 80 is adhered to the metal paste 30 and electrically connected.

As shown in FIGS. 1 and 5A, the hermetic metal paste 80 used in the step of printing the airtight metal paste (step S60) may be silver, copper, gold, platinum, palladium or at least two of the above materials. The alloy material is formed.

Further, in order to achieve airtightness, the hermetic metal paste 80 may contain metal fine particles of a material having a particle diameter of 0.8 to 1.2 micrometers or less, or 1 micrometer or less, regardless of the material of the material.

As shown in FIG. 1, FIG. 5A and FIG. 5B, the step of printing the airtight metal paste (step S60) can be performed by screen printing, such that the position of the mesh and all the metal vias 20 is completely Corresponding screens 85, and the use of a doctor blade 86 to assist in filling, the airtight metal paste 80 can be printed and fixed on the surface of the metal paste 30 where the metal vias 20 meet the first surface 11 and the second surface 12 on.

Next, please refer to the printed wires (step S70), as shown in FIGS. 1 and 6, which are printed on the first surface 11 or the second surface 12 and fixed with at least one wire. 90. The wire 90 is electrically connected to the gas tight metal paste 80 and electrically connected to the at least one metal via hole 20 to form an electric circuit.

Referring again to FIG. 1, a second sintering (step S80) is performed to sinter the substrate 10 and cure the hermetic metal paste 80 and the wires 90. The temperature profile used in the step of performing the second sintering (step S80) is also not particularly limited, and a temperature profile in which only the gas-tight metal paste 80 and the wire 90 are completely cured can be applied.

However, the second sintering step (step S80) is carried out, and if the time is too long, the metal paste 30 or the gas-tight metal paste 80 is excessively crystallized to affect the service life or the quality of use. In order to avoid the occurrence of the phenomenon that the metal paste 30 or the gas-tight metal paste 80 is excessively crystallized, the second sintering (step S80) step, the total time including the temperature rise and the temperature drop may be selected to be completed within 2 hours.

In summary, the substrate 10 formed by the method for manufacturing the hermetic metal via hole S100 has a metal paste 30 which is filled with the metal via hole 20 and is adhered to the metal paste 30 which is covered with the metal via hole 20. The gas-tight metal paste 80, together with the gas-tight metal paste 80, may contain a metal fine particle having a particle diameter of 0.8 to 1.2 micrometers or less, which can form a metal via hole, The airtightness of the metal paste 30 and the airtight metal paste 80 greatly improves the reliability of application. Further, since the process employs a sintering process in which the first sintering (step S50) and the second sintering (step S80) are performed twice, it can be applied to the raw substrate before sintering and the cooked mature substrate after sintering. The production has greatly increased the industrial applicability of the manufacturing method of the airtight metal guide hole S100.

The embodiments are described to illustrate the features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the contents of the present invention and The scope of the invention is to be construed as being limited by the scope of the appended claims.

S100‧‧‧Method for manufacturing airtight metal guide holes

S10‧‧‧ provides a substrate

S20‧‧‧ forming metal guide holes

S30‧‧‧ fill holes

S40‧‧‧ Liquid pressure equalization

S50‧‧‧First sintering

S60‧‧‧Printing airtight metal paste

S70‧‧‧Printed wire

S80‧‧‧Second sintering

Claims (10)

A method for manufacturing a gas-tight metal via hole, comprising the steps of: providing a substrate, wherein the substrate has a first surface and a second surface opposite to the first surface; forming a metal via hole, Forming a plurality of metal vias penetrating the substrate and penetrating the first surface and the second surface; filling the holes, filling each of the metal via holes with a metal paste; performing liquid pressure compaction The substrate is vacuum-coated with a coating film, and the substrate coated with a liquid fluid is uniformly coated with a specific pressure to densify the liquid, and then the coating is removed. Performing a first sintering by sintering the substrate to cure the metal paste in the metal vias; printing a gas-tight metal paste on each of the metal vias and the first surface and the first A gas-tight metal paste is printed and fixed on the surface of the two surfaces, and the air-tight metal paste is adhered to and electrically connected to the metal paste; and the printed wire is printed on the first surface or the second surface and fixed At least one wire that is electrically connected And hermetically connected to the metal paste and at least one of the metal guide hole formed on a common conductive ground circuit; and a second sintering, which line the substrate by sintering the metal paste and the lead airtight cured. The manufacturing method according to claim 1, wherein the substrate is a ceramic substrate. The manufacturing method of claim 1, wherein the metal conducting pores It is formed by laser or mechanical drilling. The manufacturing method of claim 1, wherein the step of filling the hole is performed by covering the first surface with a stencil and performing vacuum suction on the second surface, wherein the steel plate has a plurality of holes completely corresponding to the metal via holes. The manufacturing method of claim 1, wherein the specific pressure is a pressure of 100 psi or more. The manufacturing method of claim 1, wherein the printing the airtight metal paste step is performed by screen printing, and the airtight metal paste is printed and fixed to the metal vias and the first The surface and the second surface meet on the surface of the metal paste. The manufacturing method according to claim 1, wherein the hermetic metal paste contains at least a plurality of metal fine particles having a particle diameter of 0.8 to 1.2 micrometers or less. The manufacturing method according to claim 1, wherein the step of performing the second sintering is completed within 2 hours to avoid excessive crystallization of the hermetic metal paste or the metal paste. The manufacturing method according to claim 1, wherein the metal paste is formed of silver, copper, gold, platinum, palladium or at least two of the above alloy materials. The manufacturing method according to claim 1 or 7, wherein the airtight metal paste is formed of an alloy material of silver, copper, gold, platinum, palladium or at least two of the foregoing materials.