JPH05198608A - Method and device for sealing semiconductor element - Google Patents

Abstract

PURPOSE:To eliminate a gnard ring by selectively heating the sealing area of a semiconductor element and sealing the semiconductor element by softened sealing resin. CONSTITUTION:A wire bonded substrate 2 before sealing is placed on a placing table 18 and is kept at the prescribed temperature with a heater 24 for the prescribed time. As a result, only the sealing range 28 of the substrate 2 is selectively heated by a heating part 20. As for the sealing range 28 of the substrate 2, which is kept in the heated condition, softened flowing sealing resin 30 is applied by the suitable quantity by a dispenser 32 which is a resin supplying means. Since the sealing range 28 of the substrate 2 is heated to the suitable temperature, the applied sealing resin 30 is heated and the flowability is maintained and accelerated. Then, the resin 30 is made to flow into the sealing range 28 suitably and sealing is performed. Thus, the production cost is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor element encapsulation method and apparatus used for resin encapsulation of semiconductor elements such as bare chips.

Conventionally, in a hybrid integrated circuit device, a bare chip is placed on a substrate and a sealing resin is placed on the bare chip to perform resin sealing. In such a resin encapsulation, the fluidity of the encapsulating resin greatly affects the reliability of the encapsulation. If the encapsulating resin is heated to an extremely liquefied state, the fluidity will be good, but when it is supplied onto the substrate, it will flow and an appropriate lump state will not be obtained, so the required encapsulating state will be realized. I can't. That is, proper thixotropy is required.

However, if the fluidity is lowered in order to enhance the lump state, the flow on the substrate will be worse by that much, which also causes deterioration of the sealed state. Therefore, there is a method of heating the entire substrate and supplying the sealing resin on the substrate maintained at an appropriate heating temperature.
That is, it is extremely difficult to set the temperature at which the sealing resin is provided with appropriate fluidity at a temperature that does not deteriorate the characteristics of various mounted components. The allowable temperature differs for each part, and the temperature range that satisfies all of them is extremely narrow, and it is difficult to control the temperature by examining the temperature conditions therefor.

Further, conventionally, when a highly fluid sealing resin is used or has an excessive fluidity, a method of installing a guard ring as a flow stop around the element to be sealed has been adopted. However, such a method requires a step of installing a guard ring and a step of hardening the guard ring,
There is a drawback in that an increase in manufacturing man-hour causes an increase in manufacturing cost.

Therefore, it is an object of the present invention to provide a semiconductor element encapsulation method and apparatus in which a substrate is selectively heated to enable resin encapsulation.

[0006]

According to a method of sealing a semiconductor element of the present invention, a semiconductor element sealing range (2) of a substrate (2) on which a semiconductor element (bare chip 4) to be sealed is mounted.
After selectively heating (8), the semiconductor element is sealed with a sealing resin (30) in a softened state.

The semiconductor element sealing device of the present invention is
A heating unit (20) made of a material having high thermal conductivity is formed on a mounting table (18) of a substrate (2) on which a semiconductor element (bare chip 4) to be sealed is mounted, and the semiconductor is passed through this heating unit. It is characterized in that the substrate in the device encapsulation range (28) is selectively heated.

[0008]

Since the substrate in the sealing range of the semiconductor element is selectively heated, the portion to which the sealing resin is supplied is maintained at an appropriate temperature, and the fluidity of the sealing resin can be promoted. . That is, as compared with the case where the entire substrate is heated, the heating temperature condition becomes gentle, the heating is easy, and the characteristic deterioration of other parts can be prevented. Even if a sealing resin with high thixotropy is used, appropriate fluidity is obtained by heating the substrate side and the sealing resin spreads to a predetermined range near the heated portion, but the heated portion is selectively set. Therefore, the encapsulation resin can be prevented from spreading in the non-heated portion around it, and the installation range of the encapsulation resin can be controlled to an appropriate range without taking measures such as a guard ring.

Further, a heating section is selectively set on a mounting table on which a substrate to be sealed is mounted, that is, a heating section is set corresponding to a section requiring heating, and the heating section is made of a material having high thermal conductivity. By using and heating, the substrate can be selectively heated. It is possible to prevent heating to undesired locations and to prevent the sealing resin from spreading more than necessary, and to prevent the reliability of the circuit device from decreasing. In particular, since the heating part is selectively formed and there is a non-heating part, that is, a low temperature part around the heating part, the expansion of the sealing resin is suppressed at the low temperature part, so a guard for preventing the expansion. It can be expected that the ring becomes unnecessary.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor element encapsulation method and apparatus according to the present invention will be described in detail below with reference to the embodiments shown in the drawings.

1 to 5 show an embodiment of a method for encapsulating a semiconductor element and an apparatus therefor according to the present invention. As shown in FIG. 2, a bare chip 4 is installed as a semiconductor element to be sealed at a predetermined position on the surface of the substrate 2 formed of an insulating material such as glass epoxy resin (or alumina).
The bare chip 4 is fixed on the semiconductor substrate 2 with an adhesive 6 having an insulating property or a conductive property. Then, a conductor pattern 8 is formed on the surface of the substrate 2 in the peripheral portion of the bare chip 4, and each conductor pattern 8 is formed of, for example, a Cu conductor. The surface of the conductor pattern 8 is partially exposed and covered with a solder resist 10 as an insulating layer. Also, the electrode 1 of the bare chip 4
A conductor wire 16 is connected between the wire 4 and the predetermined conductor pattern 8 to make a predetermined electrical connection. For example, a gold wire is used as the conductor wire 16, and in order to connect the conductor wire 16 and the conductor pattern 6, for example, a connection pad formed by stacking nickel and gold on the connection portion of the conductor pattern 6. 17 are formed.

A mounting table 18 is used as a sealing device for performing a sealing operation on the substrate 2. The mounting table 18 also serves as a heating table, and as shown in FIG. 3, a heating unit 20 having a sealing range 28 of the substrate 2 as a heating range.
Is equipped with. The mounting table 18 of this embodiment comprises a low heating section 22 having a low thermal conductivity and a heating section 20 having a high thermal conductivity, and the low heating section 22 is made of a heat resistant organic material such as phenol resin, epoxy resin, or PTFE. The material, other insulating material, and the heating unit 20 are formed of a material having high thermal conductivity such as copper. That is, a through hole 23 corresponding to the range and position of the heated portion of the substrate 2 is formed on the mounting table 18, and the through hole 23 is formed.
The heating unit 20 is installed with a gap 25 provided in the space. In this embodiment, the through holes 23 are circular holes that surround the heating portion. A heater 24 is installed as a heating unit on the lower surface of the mounting table 18, that is, the lower surface of the heating unit 20, and the heater 24 is connected to a power source 26 equipped with an appropriate temperature control unit to supply power. .

Therefore, the substrate 2 which has been wire-bonded and has not been sealed is placed on the placing table 18 which is kept at a predetermined temperature by energizing the heater 24 for a predetermined time. as a result,
Only the sealing area 28 of the substrate 2 is selectively heated by the heating unit 20.

Next, as shown in FIG. 4, with respect to the sealing region 28 of the substrate 2 which is maintained in the heated state, the sealing resin 30 which is in a softened and fluidized state is supplied by a dispenser 32 which is a supply means thereof. Supply only appropriate amount. Substrate 2 sealing range 2
Since 8 is heated to an appropriate temperature, the supplied sealing resin 30 is heated to maintain and promote the fluidity and appropriately flow into the sealing range 28, and as shown in FIG. Is done.

By selectively heating only the sealing area 28 of the substrate 2 in this manner, the fluidity of the sealing resin 30 is maintained,
It can be promoted and efficient resin sealing can be performed. In particular, it is possible to use a resin having low fluidity, that is, a resin having high thixotropy, in view of heating the sealing range 20 to an appropriate temperature, and it is necessary to set fluidity more than necessary. There is no.

Further, by selectively heating only the sealing area 28 of the substrate 2, unnecessary heating can be prevented, other elements can be protected from overheating, and the reliability of the circuit device due to heating is lowered. Can be prevented in advance.

The mounting table 18 as a sealing device has an extremely simple structure including a heating section 20 and a low heating section 22, and selectively heats only a predetermined range by the heating section 20 which is selectively formed. The range is set, and the range to be heated of the substrate 2, that is, the sealing range 28 can be effectively heated.

In the embodiment, the low heating portion 22 is set to set the temperature difference with respect to the heating portion 20, but the low heating portion 22 is set to the non-heating portion and the low heating portion 22 is set.
The cooling water may be circulated to cool the substrate 2 to suppress the temperature rise of the non-heated portion of the substrate 2.

[0019]

As described above, according to the present invention,
The following effects are obtained. a. The fluidity of the sealing resin can be increased on the substrate, overheating outside the sealing range can be prevented, and the reliability of the circuit device can be increased. In addition, since the fluidity of the sealing resin can be controlled by appropriately setting the heating conditions, the conventional measures such as guard rings are unnecessary, and the manufacturing cost can be reduced. b. It is possible to selectively and efficiently heat the sealing area of the substrate, prevent unnecessary heating of the substrate, and prevent deterioration of reliability of the circuit device due to overheating.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a semiconductor element sealing method and apparatus of the present invention.

FIG. 2 is a vertical sectional view showing a substrate on which a semiconductor element to be sealed is mounted.

FIG. 3 is a plan view showing an overheated portion of the mounting table.

FIG. 4 is a vertical cross-sectional view showing resin sealing of a semiconductor element on a substrate.

FIG. 5 is a vertical sectional view of a hybrid integrated circuit device showing a resin-sealed substrate.

[Explanation of symbols]

 2 substrate 4 bare chip (semiconductor element) 18 mounting table 20 heating unit 28 sealing range 30 sealing resin

Claims (2)

[Claims] 1. The semiconductor element is sealed with a softened sealing resin after selectively heating a sealing area of the semiconductor element of a substrate on which a semiconductor element to be sealed is mounted. Method for encapsulating a semiconductor element. 2. A heating unit made of a material having a high thermal conductivity is formed on a mounting table of a substrate on which a semiconductor element to be sealed is mounted, and the substrate in the sealing range of the semiconductor element is passed through the heating unit. A device for sealing a semiconductor element, which selectively heats.