CN1893005A

CN1893005A - Method to prevent package components from spilling glue

Info

Publication number: CN1893005A
Application number: CN 200510081895
Authority: CN
Inventors: 刘春条; 陈大容; 李正人; 林俊良; 温兆均
Original assignee: Cyntec Co Ltd
Current assignee: Cyntec Co Ltd
Priority date: 2005-07-06
Filing date: 2005-07-06
Publication date: 2007-01-10
Anticipated expiration: 2025-07-06
Also published as: CN100394569C

Abstract

The invention relates to a method for preventing glue overflow of a packaging element, which provides a substrate with an ejector pin force application area, wherein the ejector pin force application area can apply downward force to enable the substrate to be completely contacted with a mold, and glue overflow is not generated because no gap exists between the substrate and the mold and a sealing glue body flows between the substrate and a lower mold.

Description

Prevent the method for overflow of glue of package element

Technical field

The present invention relates to a kind of formation method of potted element, more particularly a kind of method that prevents overflow of glue of package element that is applied to form potted element.

Background technology

At present relevant sphere grid array (BGA) N-type semiconductor N component package processing procedure, it mainly is that chip is attached to substrate, and make chip and substrate constitute with the routing juncture to electrically connect, the substrate that then will stick together chip more places set of molds to carry out the sealing step, chip is coated in the colloid, treat that colloid solidifies the back and takes out, again each weld pad of substrate bottom surface is planted Metal Ball and cuts moulding, and produce semiconductor element.

Yet, above-mentioned semiconductor element is in the sealing process, though the set of molds that its sizing shaped is used has the mould of high precision, but because the restriction of machining accuracy, make mold and bed die matched moulds have error afterwards, and make and have slit between composition surface between mold and the substrate, so when sealing, liquid adhesive material pours in die cavity through pressurization, the adhesive material that promptly has a little liquid state overflows in die cavity, and enter in the slit between mold and substrate, the colloid that causes overflowing can be attached on substrate or the mold.

Therefore, when the colloid that overflows is attached to substrate, because of face shaping does not meet the quality management standard, need the step through removing photoresist and repairing again, thereby the inconvenience and the processing procedure cost that increase processing procedure increase, and when removing photoresist operation, produce defective products, so that influence the product yield of this encapsulation procedure because of cutter injures substrate surface easily.

When the colloid that overflows was attached to mold, the accuracy in the time of can influencing the set of molds matched moulds so operating personnel need often cleaning mould, so that can influence the yield of manufacture procedure of adhesive, and easily made set of molds impaired, and shortens its useful life again.

In addition, mention also that in the prior art another kind prevents the method for excessive glue, it is included in has a substrate in the semiconductor encapsulating structure, an embankment, and a chip and a plurality of soldered ball form a plurality of leads and several weld pads on the surface of substrate.Embankment is taken from a lead frame and is attached to the upper surface of substrate with viscose, corresponding to the window of upper surface of base plate, overflows to prevent packing colloid.Chip is attached on the substrate with viscose, a plurality of outputs/input pad forms the center part of chip surface, and is positioned at the window on the substrate, and plural wires is in order to electrically connect substrate and I/o pad, a plurality of soldered balls then are to be set up on each weld pad, in order to electrically connect with the outside.Though the situation that prevents excessive glue that this kind mode can reach to a certain degree takes place, the embankment that is positioned on the substrate is the surface that additionally is additional to substrate, and is cumbersome on processing procedure.

Summary of the invention

The objective of the invention is to overcome the deficiencies in the prior art and defective, a kind of method that prevents overflow of glue of package element is proposed, by the external connection end around on the substrate as the thimble end, by withstanding the thimble end downwards, make and contact fully between substrate and the mould, and exist between substrate and the mould without any the space, make that after the encapsulating, the phenomenon that does not have the glue that overflows takes place.

For reaching above-mentioned purpose, the invention provides a kind of method that prevents excessive glue, this method comprises:

Substrate with a chip is provided, and this substrate has a plurality of external connection end and this chip and this substrate and electrically connects;

Set of molds with a die cavity is provided, and this set of molds has a mold and a bed die, and this die cavity can ccontaining this substrate;

This substrate is placed in the die cavity of this bed die;

Carry out a matched moulds step, this mold combines with this bed die;

Withstand these a plurality of external connection end of this substrate downwards, make this substrate contact fully with this time die cavity, and without any the space between this substrate and this time die cavity; And

Pour into have insulate heat solidity composite properties an adhesive body between this substrate and this set of molds, wherein this adhesive body covers between the upper surface of mold and this substrate, and this substrate around.

Provide substrate because this method comprises, on substrate, have chip and plural wires in order to electrically connect substrate and chip with a plurality of external connection end.Then, provide the set of molds of a sealing shaping usefulness, and set of molds is made of a mold and a bed die, and the size of the die cavity between mold and bed die can ccontaining substrate.Then, substrate is placed in the bed die, make a plurality of external connection end around this substrate can expose to bed die around.Carry out a matched moulds step then, mold is combined with bed die.Then, withstand the external connection end of substrate downwards, make between substrate and the mould to contact fully by thimble.Then, carry out an encapsulating step and since between substrate and the mould without any the space can allow adhesive body flow between substrate and the bed die, therefore when matched moulds, the situation that does not have the glue that overflows takes place.

Description of drawings

Fig. 1 is disclosed technology according to the present invention, and expression prevents the flow chart of the method for excessive glue;

Fig. 2 A to Fig. 2 B is disclosed technology according to the present invention, and expression prevents each step schematic diagram of excessive gluing method.

Symbol description among the figure

1-6 prevents the steps flow chart of the method for excessive glue

10 substrates

12 external connection end

14 thimble application of force zones

20 bed dies

22 times die cavitys

30 adhesive materials

Embodiment

Some embodiments of the present invention can be described in detail as follows.Yet except describing in detail, the present invention can also be widely implements at other embodiment, and scope of the present invention do not limited, and its scope with claims is as the criterion.

See also Fig. 1 is applied to the method that prevents excessive glue of potted element for the present invention is disclosed flow chart of steps.Step 1 expression provides the substrate with a plurality of external connection end.Step 2 expression provides the set of molds with a die cavity, and this set of molds comprises the mold with upper mould cave, and the bed die with following die cavity.Step 3 expression is placed in substrate in the following die cavity of bed die, is positioned at substrate a plurality of external connection end all around and can exposes to bed die all around.Then, carry out a matched moulds step, mold is combined with bed die, withstand the external connection end of substrate simultaneously downwards, make substrate contact fully with mould in step 4.Then, adhesive body is poured in the die cavity of set of molds,, therefore between substrate and bed die, can allow adhesive body flow into, therefore do not have the phenomenon generation of the glue that overflows without any the space owing to contact fully between substrate and the mould in step 5.At last,, carry out a curing schedule, finish encapsulation step to solidify adhesive body in step 6.

Next, Fig. 2 A to Fig. 2 B is the step schematic diagram that prevents excessive glue represented according to the above-mentioned steps flow chart.At first, please refer to Fig. 2 A, expression has the vertical view of the substrate of a plurality of external connection end.More comprise a chip (not expression in the drawings) on this substrate 10, this chip can be routing chip or crystal covered chip.If this chip is the routing chip, then then be to electrically connect between chip and the substrate 10 by plural wires (not expression in the drawings); If chip is a crystal covered chip, then crystal covered chip then is by electrically connecting between plurality of solder projection and the substrate 10.

In addition, substrate 10 also comprises one or a plurality of external connection end 12, and these external connection end 12 can be made of lead frame (lead-frame), and these lead frames can be to be shaped on the substrate 10.The purpose of these external connection end 12 more comprises the thimble application of force zone 14 that contacts with mould as with substrate downwards except electrically connecting with electronic component.When thimble withstands the external connection end 12 of substrate 10 both sides downwards, because substrate 10 contacts fully with the following die cavity 22 of bed die 20, this means, between substrate 10 and following die cavity 22 without any the space existence, and when follow-up encapsulating step, adhesive body can't flow between substrate and the following die cavity.When also can or not making tolerance and cause excessive glue because of the tolerance of application of force inequality, size supplied materials.

In addition, the material in these external connection end 12 and thimble application of force zone 14 can be that metallic plate or metal derby are formed, or nonmetallic materials constitute.What deserves to be mentioned is that the material of substrate 10 can be dielectric material, insulating material, also or by following form selected material: the hybrid system of metal, single face comprise the hybrid system and the two-sided hybrid system that comprises metal of metal.

Then, please refer to Fig. 2 B.In Fig. 2 B, the part of solid line is represented following die cavity 22, and in order to ccontaining substrate 10, the size of therefore following die cavity 22 can correspond to the size of substrate 10.

Then, be feature of the present invention, carry out a matched moulds step, make mold combine with bed die 20, simultaneously, thimble withstands the external connection end 14 of substrate 10 downwards, make substrate 10 can contact completely, do not exist and do not have any space with the following die cavity 22 of bed die 20.Because, between substrate 10 and following die cavity 22 without any the space, this makes follow-up when irritating the mould step, adhesive body 30 can't flow between substrate 10 and the following

die cavity

22,30 of adhesive bodies are present between the upper surface of mold and substrate 10, therefore when sealing, the phenomenon that does not have the glue that overflows takes place.Wherein, adhesive body 30 can be an insulate heat solidity compound, for example silica packing material (silica filler) or epoxy resin (epoxy).

At last, carry out one again and solidify (curing) step, to solidify adhesive body 30, make the upper surface of substrate 10 and all around, and the element that is positioned on the substrate 10 is coated simultaneously by adhesive body 30.In addition because between substrate 10 and the following die cavity 22 without any the existence in space, do not have the below that there is substrate 10 in any adhesive body 30, so the lower surface of substrate 10 then is to expose out.

The above is preferred embodiment of the present invention only, is not in order to limit claim scope of the present invention; All other do not break away from the equivalence of being finished under the disclosed spirit and changes or modification, all should be included in the scope of claims.

Claims

1. A method for preventing packaging components from overflowing glue, characterized in that the method comprises:

providing a substrate with a chip, the substrate has a plurality of external terminals and the chip is electrically connected to the substrate;

providing a mold set with a mold cavity, the mold set has an upper mold and a lower mold, and the mold cavity can accommodate the substrate;

accommodating the substrate in a lower mold cavity of the lower mold;

Execute a mold closing step, the upper mold is combined with the lower mold;

Pressing down against the plurality of outer ends of the substrate so that the substrate is in full contact with the lower cavity without any gap between the substrate and the lower cavity; and

Pouring an insulating thermosetting compound between the base plate and the mold set, wherein the sealant covers the space between the upper mold and the upper surface of the base plate, and the periphery of the base plate.

2. The method for preventing glue overflow of packaging components as claimed in claim 1, wherein the material of the substrate is selected from one of the following groups: dielectric materials, insulating materials, metal composite systems, and composite systems containing metal on one side Or composite systems containing metal on both sides.

3 . The method for preventing glue overflow of package components as claimed in claim 1 , wherein the way of electrically connecting the chip to the substrate is selected from one of the following groups: a plurality of wires or a plurality of solder bumps.

4 . The method for preventing glue overflow of package components as claimed in claim 1 , wherein the materials of the plurality of external terminals are selected from one of the following groups: a lead frame or a lead frame integrally formed on the substrate.

5. The method for preventing glue overflow of packaging components as claimed in claim 1, wherein the insulating thermosetting compound is selected from one of the following groups: epoxy resin or silicone filling material.

6. A method for preventing packaged components from overflowing glue, characterized in that the method comprises:

A substrate is provided, with at least one pair of thimble force application areas located on both sides of the substrate;

accommodating the substrate in the lower mold cavity of the lower mold, and the ejector pin force application area of the substrate is exposed to the outside of the lower mold;

performing a mold closing step so that the upper mold is combined with the lower mold;

Press down against the force application area of the thimble, so that the substrate is in full contact with the lower mold cavity without any gaps;

pouring an encapsulant having properties of an insulating thermosetting compound into the substrate and the mold set; and

The sealant is cured, and the sealant only covers an upper surface of the substrate and the periphery of the substrate, while exposing the lower surface of the substrate.

7. The method for preventing glue overflow of packaging components as claimed in claim 6, wherein the material of the substrate is selected from one of the following groups: dielectric materials, insulating materials, metal composite systems, and composite systems containing metal on one side Or composite systems containing metal on both sides.

8 . The method for preventing glue overflow of packaged components as claimed in claim 6 , wherein the material of the force-applying region of the ejector pin is integrally formed on the lead frame of the substrate.

9. The method for preventing glue overflow of packaging components as claimed in claim 6, wherein the insulating thermosetting compound is selected from one of the following groups: epoxy resin or silicone filling material.