CN1821788B - Embedded microcontact element and manufacturing method thereof - Google Patents

Abstract

An embedded micro-contact element is made by a micro-electromechanical process. The embedded micro-contact element includes: a cantilever, which can define a first long side and a second long side facing away from the first long side; a needle tip portion, which is connected to one end of the first long side and extends in a vertical direction to the cantilever; and an embedded portion, which is vertically extended from the second long side.

Description

Embedded microcontact element and manufacturing method thereof

technical field

The present invention is related to a micro-contact element, and more specifically refers to an embedded micro-contact element and a manufacturing method thereof.

Background technique

When testing high-density or high-speed electrical devices such as LSI or VLSI circuits, a probe card Probe Card with a large number of micro-contact element probes must be used to provide a flexible and electrical connection through the micro-contact element Conductor characteristics, as an element that is electrically connected to the object to be tested, such as a test contact element for LSI and VLSI chips, semiconductor wafers, chip burn-in, packaged semiconductor devices, and printed circuit boards. Of course, the micro-contact element can also be used as the IC lead of the IC package. However, for the convenience of subsequent description, the micro-contact element is mainly described as a probe as a probe card.

Generally, micro-contact elements have different shapes according to their needs. One of them is a cantilever-type micro-contact element. Due to its high elasticity, the cantilever-type micro-contact element can still be connected when it is allowed to deflect when it contacts with a foreign object. status.

As far as the probe is concerned, as shown in the patent case of US Patent No. US6268015, as shown in FIG. After a unit is manufactured, it is assembled by bonding; the precision of the bonding assembly process is worse than that of the photolithography process, and multiple bonding will cause the positioning deviation of the needle tip 1 to be enlarged or the cantilever beam 2 and the pillar 3 to be enlarged due to the accumulation of alignment errors. Joint point errors, which in turn lead to disadvantages such as poor probe position and poor consistency of probe performance.

There is another patent case such as U.S. Publication No. US20010012739, which also makes the structure of the probe by depositing metal by micro-electromechanical technology, and its tip is joined by welding, and its pillar (i.e., the bottom of the needle) is welded. The structure of the pillar is strengthened by electroplating metal on the outside of the wire method. The production speed of the pillar by wire bonding is not only quite slow, but also the manufacturing process is complicated, and precise precision control is required to make it difficult to manufacture.

Another example is U.S. Patent No. US6399900, which also uses micro-electromechanical technology to make a probe structure by deposition. The tip of the needle is welded to one end of the needle body, and the other end of the needle body is bonded to the surface of the substrate. , its stability is poor, and it may be detached from the substrate due to material fatigue under repeated operations, and the needle tip needs to be welded in a very precise manner. If there is a deviation in the welding position, the contact force of the needle tip will be uneven.

Furthermore, as in the U.S. Patent No. US6414501 patent case, it manufactures the probe by etching the silicon substrate by micro-electromechanical technology, and then coats the outside of the probe with a conductive film and then bonds with the substrate; but, Most of the probe part is made of silicon substrate, and the thickness of the conductive film is quite thin. Only the surface of the probe structure made of silicon substrate is coated, so its current tolerance is not high enough to meet the needs of high flow , and because the flexible structure of the probe is mainly made of single crystal silicon, it is easy to be brittle and cannot be repaired.

Secondly, in the case of US Patent Nos. US4961052, US5172050, and US5723894, they all directly etched silicon-based plates to make probes from single-crystal silicon, and then made probes from silicon-based plates. The probe is coated with a conductive film to provide electrical connection; however, since the conductive film cannot withstand high flow requirements, and the probe is mainly made of monocrystalline silicon, it has the disadvantage of being easily brittle and irreparable.

In addition, the U.S. Patent No. US5974662 is a plane adjustment mechanism, which can be adjusted horizontally by using several plane fine-tuning during assembly, and in order to keep all circuits in good condition during adjustment. In the contact state, several layers of elastic probes must be added between the probes and the electronic substrate; however, this structure is too complex and the transmission path of the circuit is long and it is not suitable for high-frequency transmission.

Contents of the invention

In view of this, the main purpose of the present invention is to provide an embedded micro-contact element and its manufacturing method, which can make the position of the needle point and the positioning reference of the joint part the same, improve the overall assembly accuracy and improve the overall performance by a single joint consistency.

Another object of the present invention is to provide an embedded micro-contact element and its manufacturing method. The micro-contact element is integrally formed with high precision.

Another object of the present invention is to provide an embedded micro-contact element and its manufacturing method. The micro-contact element is embedded in the substrate, which can provide better supporting force and provide auxiliary positioning effect.

Another object of the present invention is to provide an embedded micro-contact element and a manufacturing method thereof, and the micro-contact element has relatively high current tolerance.

Another object of the present invention is to provide an embedded micro-contact element and its manufacturing method, the probes of which have high electrical conductivity and fatigue resistance.

The next object of the present invention is to provide an embedded micro-contact element and its manufacturing method, the signal transmission of the micro-contact element is shorter, which is beneficial to high-frequency transmission.

In order to achieve the above object, the present invention provides an embedded micro-contact element, which is made by micro-electromechanical process. The embedded micro-contact element includes: a cantilever, which can define a first long side and a The second long side facing away from the first long side; a needle point is connected to one end of the first long side and extends in a direction perpendicular to the cantilever; an embedded part is formed from the first long side It is formed by extending vertically on the two long sides.

In order to have a further understanding and recognition of the features and objectives of the present invention, the following preferred embodiments are listed below, which will be described in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a kind of schematic diagram of existing probe structure;

2a to 2ff are schematic diagrams of the manufacturing process of the first preferred embodiment of the present invention;

3a to 3k are schematic diagrams of the manufacturing process of the second preferred embodiment of the present invention;

Fig. 4 is the perspective view of the second preferred embodiment of the present invention;

Fig. 5 is a perspective view of another embodiment shown in Fig. 4;

6 to 7 are schematic diagrams of the assembly process of the third preferred embodiment of the present invention;

8 is a schematic diagram of a fourth preferred embodiment of the present invention;

Fig. 9 is a schematic diagram of a fifth preferred embodiment of the present invention;

Fig. 10 is a schematic diagram of a first preferred embodiment of the present invention;

11 to 13 are schematic diagrams of different implementation aspects of the present invention;

Fig. 14 is a perspective view of a third preferred embodiment of the present invention;

15 to 17 are schematic views of different embodiments of the present invention.

Detailed ways

Please refer to Fig. 2a to Fig. 2ff, it is the manufacturing method of the embedded micro-contact element provided by the first preferred implementation of the present invention, its steps include:

(A) As shown in FIG. 2a, take a base plate 11, which is a single silicon crystal plate.

(B) As shown in FIG. 2 b , deposit a dielectric film 12 on the substrate 11 . The dielectric film 12 is a film made of silicon nitride and can be coated on it by low pressure chemical vapor deposition (LPCVD).

(C) As shown in Figure 2c, a first masking layer 13 is coated on the dielectric film 12, and an opening is formed in the first masking layer 13, that is, the photolithography process in the semiconductor manufacturing process of the lithographic etching process is carried out .

(D) As shown in FIG. 2d, the dielectric film 12 in the opening is removed. Its removal method can utilize reactive ion etching (RIE).

(E) As shown in FIG. 2e, remove the first masking layer 13 and use anisotropic etching, such as potassium hydroxide (KOH), to etch the substrate 11 that is not covered by the dielectric film 12, so that The substrate 11 is formed with an inverted pyramid-shaped notch 111 .

(F) As shown in FIG. 2f, the dielectric film 12 is removed. The dielectric film 12 can be removed by a hot phosphoric acid etching process or a reactive ion etching process (RIE). The etching material and conditions are selected and will not have any impact on the substrate.

(G) As shown in FIG. 2g , coating a conductive film 14 on the surface of the substrate 11 . The material of the conductive film can be titanium metal, and the method of coating the conductive film 14 can be completed by deposition methods such as sputtering, vapor deposition and electroplating.

(H) As shown in FIG. 2 h , coat a second shielding layer 15 on the surface of the conductive film 14 , and form an opening corresponding to the notch 111 of the substrate 11 in the second shielding layer 15 .

(I) As shown in FIG. 2 i , coat one to several layers of strengthening films 16 on the second shielding layer 15 and the conductive film 14 located in the gap 111 . The strengthening film 16 has properties of abrasion resistance, low stickiness, and good electrical conductivity, such as rhodium metal.

(J) As shown in FIG. 2j , remove the second masking layer 15 . The second shielding layer 15 can be removed by etching, and the reinforcement film 16 coated on the second shielding layer 15 is also removed.

(K) As shown in FIG. 2k , a third shielding layer 17 is formed on a partial position of the conductive film 14 . Wherein the third shielding layer 17 is formed on the notch 111 and two local positions on the same side.

(L) As shown in Figure 21, a first support material 18 is deposited on the conductive film 14 on the conductive film 14, wherein the first support material 18 can be a copper metal material or a polymer material, and it is deposited The method can be sputtering, evaporation, electroforming or coating.

(M) As shown in FIG. 2m , removing the third masking layer 17 to form a notch 19 formed in the first support material 18 after removing the third masking layer 17 .

(N) As shown in FIG. 2n , deposit a first electroforming material 21 in the recess 19 of the first support material 18 , wherein the first electroforming material 21 can be nickel metal.

(O) As shown in FIG. 2o, the surface layers of the first electroforming material 21 and the first supporting material 18 are simultaneously leveled.

(P) As shown in FIG. 2p, a fourth masking layer 22 is coated on the first electroforming material 21 above the gap 111, so that the patterned fourth masking is produced by the existing lithographic etching process. Layer 22.

(Q) As shown in FIG. 2q, a sacrificial layer 23 is deposited on the top layer, wherein the sacrificial layer 23 can be titanium metal. The deposition method can be sputtering, vapor deposition, electroplating and the like.

(R) As shown in FIG. 2 r , the fourth shielding layer 22 is removed, so that only the sacrificial layer 23 is not coated on the first electroforming material 21 located in the gap 111 .

(S) As shown in FIG. 2 s , coat a continuous fifth shielding layer 24 with openings on the top of the first electroforming material 21 .

(T) As shown in FIG. 2 t , a second supporting material 25 is disposed in the opening of the fifth shielding layer 24 by electroforming on the top layer.

(U) As shown in FIG. 2u, the fifth masking layer 24 is removed.

(V) As shown in FIG. 2v, deposit a second electroforming material 26 in the groove formed after removing the fifth masking layer 24, and grind the second electroforming material 26 and the second supporting material 25 flat.

(W) As shown in FIG. 2 w , a sixth shielding layer 27 is disposed on the top layer, and an opening is formed in the sixth shielding layer 27 relative to the second position and the third position.

(X) As shown in FIG. 2x , deposit a bonding metal layer 28 in the opening of the sixth shielding layer 27 . The bonding metal layer 28 can be made of one or several metal materials with good adhesion, and the bonding metal layer 28 can also be composed of a single or several layers of materials. The deposition method of the bonding metal layer 28 may be vapor deposition, sputtering or electroplating.

(Y) As shown in FIG. 2y , unblock the sixth masking layer 27 .

(Z) As shown in FIG. 2z, a seventh shielding layer 29 is arranged between the bonding metal layer 28 at the second position and the bonding metal layer 28 at the third position, and the seventh shielding layer 29 is slightly covered The edge of each metal layer 28 is bonded.

(AA) As shown in FIG. 2aa, a third support material 31 is deposited.

(BB) As shown in FIG. 2bb, the seventh shielding layer 29 is removed.

(CC) As shown in FIG. 2cc, after removing the seventh masking layer 29, deposit a third electroforming material 32 in the concave hole formed in the third support material 31, and grind and level the third support material 31 and The upper surface of the third electroforming material 32 .

(DD) As shown in FIG. 2dd , the process from (Z) to (C1) is repeated several times until the electroforming material is stacked to a predetermined height.

(EE) As shown in FIG. 2ee, the embedded micro-contact element can be obtained by removing each support material. As shown in FIG. 2ff, it is a perspective view of the formed embedded micro-contact element. Then, the conductive film 14 is etched away to separate the formed embedded micro-contact element from its substrate.

It is specifically stated here that the above-mentioned first to seventh shielding layers can be made of photoresist material.

As shown in FIG. 2ff, the embedded micro-contact element 100 has a cantilever 41 formed by electroforming material, and the cantilever 41 can define a first long side 411 and a side facing away from the first long side 411 The second long side 412 of the cantilever 41; a needle tip base 42 connected to one end of the first long side 411 of the cantilever 41 and extending in a direction perpendicular to the cantilever 41; a cone formed on the free end of the needle tip base 41 Shaped needle tip 43; two joint auxiliary parts 44 extending in the same direction as the needle tip 43, and each joint auxiliary part 44 is located on the other end of the first long side 411; an embedded part 45 is from the first long side 411 The two long sides 412 extend on the extension line between the two joining auxiliary parts 44 ; the two joining parts 46 are formed on two sides of the embedded part 45 .

Wherein, the cantilever 41 can also be composed of multiple metal layers, so that the metal cantilever has good electrical conductivity and mechanical fatigue resistance.

In addition, in the process of forming the cantilever, polysilicon material deposited by plasma enhanced chemical vapor deposition (PECVD) can be changed or added, because polysilicon material has good mechanical fatigue resistance, which can make up for the shortcomings of general good conductive metals .

Furthermore, metal and dielectric materials can also be laminated on the outside of the cantilever, so that the signal transmission outer layer has more than one insulating shielding layer and a grounded conductive layer, or the cantilever can be made of polymer materials.

Please refer to Fig. 3a to Fig. 3k, which is a manufacturing method of embedded micro-contact element base 200 provided by the second preferred embodiment of the present invention, the steps include:

(A) As shown in Figure 3a, get a silicon-based plate 51, and the inside of this silicon-based plate 51 has formed a silicon dioxide interlayer 56 (SI02) by deposition, and then on the silicon-based plate 51 A first shielding layer 52 is respectively arranged on the top and bottom surfaces. The first shielding layer 52 can be made of silicon dioxide, photoresist material, silicon nitride or aluminum metal. The first shielding layer 52 can be made of The photolithography process is laid out. The silicon-based plate 51 including the silicon dioxide interlayer 56 can be formed by bonding two single-crystal silicon wafers to each other with a silicon dioxide layer.

(B) As shown in FIG. 3 b , a second shielding layer 53 with patterned openings is laid on the first shielding layer 52 on the top surface of the silicon substrate 51 . The second shielding layer 53 can be a photoresist material.

(C) As shown in Figure 3c, the first shielding layer 52 located in the opening of the second shielding layer 53 is etched away by reactive ion etching (RIE) of the first shielding layer 52 on the top surface; and after etching, The second shielding layer 53 is removed.

(D) As shown in FIG. 3 d , laying a patterned third masking layer 54 on the silicon substrate 51 . The program for laying out the graphical third shielding layer includes:

First coat an original continuous layer made of silicon dioxide, photoresist material, silicon nitride or aluminum metal material on the top surface of the silicon base plate 51, and then place the original continuous layer on the predetermined position where the original continuous layer is to be left Lay out a cover layer, and perform reactive etching to remove the original continuous layer not covered by the cover layer, and remove the cover layer after removing the original continuous layer at the predetermined position, leaving only the predetermined The position of the original continuous layer makes it a third masking layer with patterned openings. Since the process of forming the patterned third masking layer is a prior art, it will only be briefly discussed.

(E) As shown in FIG. 3 e , pattern the first masking layer 52 on the bottom surface of the silicon base plate 51 , in other words, form a gap in the first masking layer 52 on the bottom surface of the silicon base plate 51 .

(F) As shown in Figure 3f, a fourth shielding layer 55 is laid on the top surface of the silicon base plate 51, and the fourth shielding layer 55 is formed with an opening opposite to the opening between the third shielding layer 54, that is The opening of the fourth shielding layer 55 directly communicates with the silicon substrate 51 . The fourth shielding layer can be laid by photolithography process in semiconductor process.

(G) As shown in FIG. 3g, the silicon base plate 51 not covered by the fourth masking layer 55 is etched with inductively coupled plasma ion until the silicon dioxide interlayer 56 is exposed, so that the top surface of the silicon base plate 51 is formed An embedding groove 511 is provided.

(H) As shown in FIG. 3 h , the silicon dioxide interlayer 56 located in the embedding groove 511 is etched with reactive ions, and the fourth masking layer 55 is removed.

(1) As shown in Fig. 3 i, the silicon base plate 51 is etched with inductive plasma ion, so that the embedding groove 511 of the silicon base plate 51 is deepened to a predetermined depth, and the top surface of the silicon base plate 51 is not affected by the first and second plates. The parts covered by the three masking layers 52 and 54 are also etched until the silicon dioxide interlayer 56 is exposed, so that a cavity 512 is formed on the top surface of the silicon base plate 51 .

(J) As shown in FIG. 3j , the third masking layer 54 and the later exposed silicon dioxide interlayer 56 are removed by reactive ion etching.

(K) As shown in FIG. 3k, the top surface of the silicon substrate 51 is etched with inductive plasma ion, so that a joint groove 513 is formed on the top edge periphery of the embedding groove 511, and the embedding groove 511 is connected with the container groove at the same time. 512 is deepened, and the embedding groove 511 is etched from the top surface of the silicon substrate 51 to the bottom surface thereof.

In this way, the manufacturing process of the embedded micro-contact element base 200 is completed, please refer to FIG. 4 , which is a perspective view of the base 200 .

Of course, as shown in FIG. 5 , the base 200 can also be manufactured with the grooves required for assembly on the substrate that has completed circuit wiring by using machining technology on the existing ceramic substrate technology and organic material substrate, The base 200 is made into a circuit board with assembly grooves on its surface. The positioning structure 61 with a dielectric surface can also be stacked on the ceramic substrate or the organic material substrate with semiconductor technology, and the circuit wiring 62 can be included in the ceramic substrate or the organic material substrate.

Please refer to Fig. 6 to Fig. 7, it is the combination mode between the embedded micro-contact element 100 and the embedded micro-contact element base 200 provided by the third preferred embodiment of the present invention, please refer to Fig. 6 first, the embedded micro-contact element The embedding part 45 of 100 is directly penetrated into the embedding groove 511 from the joint groove 513 of the embedded micro-contact element base 200, and at the same time, the joint metal layer 28 and the embedded micro-contact element base 200 are joined by welding. The metal layer 28 serves as a medium for electrical connection between the embedded micro-contact element 100 and the embedded micro-contact element base 200 . Referring to FIG. 7 again, the sacrificial layer 23 of the embedded micro-contact element 100 is removed by etching, so that the substrate 11 and the auxiliary joint portion 44 can be separated from the cantilever 41 and the tip portion 43 .

In this way, the embedded micro-contact element 100 can be partly embedded in the embedded micro-contact element base 200 to make a stable combination with the embedded micro-contact element base 200 .

So far, the embedded micro-contact element of the present invention not only has the advantage of high positioning accuracy of the junction between the needle tip and the embedded micro-contact element base, but also has the main contact point close to the top layer, and the needle body is hidden in the surface layer, which can make maintenance and replacement of needles easier. It will not damage the needle body and has the advantage of easy maintenance and operation. At the same time, both the cantilever and the needle point of the embedded micro-contact element of the present invention are made of conductors, and the electric current tolerance thereof is good.

Of course, as shown in FIG. 8 , when the length of the embedding portion 45 of the embedded micro-contact element is insufficient to penetrate the groove 511 of the embedded micro-contact element base 200, a conductive groove can be filled in the embedding groove 511 of the embedded micro-contact element base 200. The material 63 can serve as a medium for the embedded micro-contact element 100 to communicate with the external circuit 70 .

Also as shown in FIG. 9, if the embedded micro-contact element base 200 is provided with circuit wiring 64, the bonding metal layer 28 of the embedded micro-contact element 100 can be connected to the circuit wiring 64 to connect with the external circuit 70. At this time, the embedding groove 511 can choose a structure that does not penetrate the bottom surface of the silicon substrate 51 , and its depth is enough to accommodate the embedding portion 45 .

Please refer to FIGS. 10 to 13, wherein the embedding portion 45 (as shown in FIG. 10 ) of the embedded micro-contact element 100 of the present invention can also be changed to elastic elastomeric structures 45', 45", 45"'( As shown in Figures 11 to 13), the direction of elastic deformation will be perpendicular to the plane of the base plate, but the elastomeric structure process can use the similar process of the first preferred embodiment shown in Figure 2, through multi-layer electroforming and flattening The elastic structures 45 ′, 45 ″, 45 ″′ can be further electrically connected with external circuits by contacting or bonding.

Please refer to Fig. 14 to Fig. 17, wherein the cantilever 41 of the embedded micro-contact element 100 of the present invention can also be changed from a rigid rectangular body to a pivot structure 41', 41", 41 with adjustable cantilever rigidity in the middle section. ”’ (as shown in Figure 15 to Figure 17), so that when the usable design area is too small or the thickness dimension is limited, and it is desired to achieve a larger deformation of the needle tip, the contact force change of the needle tip can be accepted In small cases, the purpose can be achieved by using a cantilever with a pivot structure; the rigidity of the embedded micro-contact elements of different sizes can also be adjusted to be consistent by reducing the rigidity of the overall cantilever structure through the pivot structure.

Claims (5)

1. the package assembly of embedded type micro contact element and embedded type micro contact element pedestal is characterized in that, includes:

One embedded type micro contact element has a cantilever, a needle tip and an Embedded Division; This cantilever can define one first long side and second long side back on this first long side, this needle tip is to be connected in this first long side, one end and to extend in vertical direction with this cantilever to form, and this Embedded Division is that vertical extension of institute forms on this second long side;

One embedded type micro contact element pedestal has a base version, an embedded groove, a tank and an engaging groove; This tank is to extend a predetermined width and a distance downwards to form from end face one place of this base version, and this engaging groove is to extend downwards from another place of the end face of this base version to form, and this embedded groove is to extend downwards in the bottom of engaging groove institute to form; The Embedded Division of this embedded type micro contact element is penetrated in this embedded groove, and this cantilever then part is placed in this engaging groove, and the part that this cantilever is not placed in this engaging groove is suspended in this tank.

2. according to the package assembly of described embedded type micro contact element of claim 1 and embedded type micro contact element pedestal, it is characterized in that, be filled with a conductive material in the embedded groove of described this embedded type micro contact element pedestal, enable the media that is communicated with external circuit as this embedded type micro contact element.

3. according to the package assembly of described embedded type micro contact element of claim 2 and embedded type micro contact element pedestal, it is characterized in that described this embedded type micro contact element and embedded type micro contact element pedestal are by being stable on the element that possesses external circuit by this conductive material.

4. according to the package assembly of described embedded type micro contact element of claim 1 and embedded type micro contact element pedestal, it is characterized in that, described this embedded type micro contact element base interior is provided with some wirings, makes this embedded type micro contact element can be by being connected with this wiring and the circuit turn-on in the external world.

5. according to the package assembly of described embedded type micro contact element of claim 4 and embedded type micro contact element pedestal, it is characterized in that described this embedded type micro contact element pedestal possesses the circuit board of assembling groove for the surface.

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