CN1361725A

CN1361725A - Diaphragm Test System

Info

Publication number: CN1361725A
Application number: CN99816816A
Authority: CN
Inventors: G·K·雷德; K·A·史密斯; M·A·拜尼; T·莱舍尔; M·科克斯
Original assignee: Cascade Microtech Inc
Current assignee: FormFactor Beaverton Inc
Priority date: 1999-07-21
Filing date: 1999-07-21
Publication date: 2002-07-31
Anticipated expiration: 2019-07-21
Also published as: AU5224499A; KR100724131B1; JP2003505871A; KR20020027483A; CN1174836C; EP1210208A1; EP1210208A4; WO2001007207A1

Abstract

The substrate (200) is preferably constructed of a malleable material and the tool (210) has the shape required for the final device to be brought into contact with the contact pads on the test device, the tool being brought into contact with the substrate. The tool is preferably constructed of a material that is harder than the substrate so that the depressions (216) can be easily made in the substrate. Preferably, a patterned non-conductive (insulating) layer is supported by the substrate. Conductive material is placed in the recess and then preferably polished to remove excess from the top surface of the non-conductive layer and provide a flat overall surface. The traces are patterned on the non-conductive layer and the conductive material. The polyimide layer is then preferably patterned over the entire surface. The substrate is then removed by any suitable process.

Description

Membrane probing system

The background of invention

The present invention relates to be generally used for check the gauge head assembly of the sort of type of integrated circuit (IC), and specifically, the present invention relates to have the Membrane probing assembly of contact, these contacts are with nuzzle up each I/O conductor of every table apparatus of the mode of part control, so that wipe the oxide on surface that is present in usually on those conductors reliably clear, guarantee that thus test suite is connected with good electrical between every table apparatus.

Particularly the development trend that soft copy is produced in the integrated circuit technique is towards the more and more littler direction of physical dimension, and wherein very a large amount of discrete circuit elements is fabricated on single substrate or " wafer ".After the processing, this wafer is divided into several rectangular dies or " little circuit wafer (die) ", and each little circuit wafer is rendered as metallization contact pins structure rectangle or Else Rule, carries out I/O by this pad and connects.Though each little circuit wafer is separately to pack at last, for the purpose of raising the efficiency, makes the check of the circuit on each little circuit wafer and preferably finishes when each little circuit wafer still links together on wafer.A kind of typical program is that wafer supporting is gone up and moved wafer with respect to the head of test suite at X, Y and Z direction at platform or " chuck ", makes that each contact on the test suite moves to another little circuit wafer to engage continuously with each little circuit wafer from a little circuit wafer.Each holding wire, power line and ground wire lead to test suite from check meter, so each circuit sequentially is connected on the check meter.

Be used to check the test suite of a kind of traditional form of integrated circuit to have a plurality of contacts of needle-like tip.These tips are installed on to be made around the central opening on the test board, so that radially inwardly compile and pass this opening down.Exceed certain when point when wafer is elevated to, the pad on this some place wafer at first enters with these tips and contacts, and these tips are crooked up so that slip over their pads separately forward, remove the oxide that is accumulated on the pad thus.

The problem of the test suite of this form is that high inductance appears in the narrow geometry owing to the needle-like tip, makes that distorted signals is serious in the high frequency measurement that is undertaken by these tips.Also have, when these tips nuzzled up their separately pads, their mode of action picture sharpener tool of satisfying caused the pad excessive damage thus.This problem expands the crooked degree out of shape of test tip between the operating period; Perhaps can not end on the contrary on public its plane, this causes more tip forward to cross the important place pressing to their pads separately.Also have, the spacing of the center to center of these tips is mounted to less than 100 microns or the many rows of one-tenth grid-like pattern, arrange that with the pad that adapts to the more stylish little circuit wafer of more high density this is unpractical.Also have, the wiping length of the needle-like tip of the test suite of this form is 25 microns or longer, and this has increased the difficulty in the test zone that remains on permission.

In order to reduce inductance loss, the wearing and tearing of reduction pad and adaptation physical dimension than dingus, developed the test suite of second kind of form, it uses flexible diaphragm structure to support test contact.In this assembly, the lead-in wire of the good geometry that limits is formed on one or more layers flexible insulation film this film such as polyimides or MYLAR ^TMIf use each layer that separates, these layers are combined together to form for example transfer wire structure of multilayer.At the structure of this flexibility or the middle body of diaphragm, every lead usefulness test contact separately is as end points, and this contact is made outwards protruding out on the outer surface of diaphragm and from this outer surface.These test contact are arranged to and install the predetermined pattern that the pattern of pad matches, and generally are to make the projection of having alarmmed to test the flat surfaces that is limited by pad usually.The inner face of diaphragm is bearing on the supporting structure.This supporting structure can be taken as for example form of truncated pyramid, in the case, the inner face of diaphragm core is bearing in the truncated end portion of this supporting structure, and the marginal portion of diaphragm is to be pulled away from core with core angledly, to remove any setting composition that may center on the pad on the device.

About the Membrane probing assembly of describing just now, geometry by careful selection lead-in wire is eliminated excessive line inductance, and preferably use photoetching process, so that can carry out some controls, to adapt to the structure of higher density to size, interval and the layout of test contact.Yet, though proposed some multi-form this test suites, but the assembly of this form is reducing pad wearing and tearing and is realizing removing reliably oxide skin(coating) from each device pad aspect fully being electrically connected between the device guaranteeing assembly and testing, experience difficulties.

A kind of Membrane probing assembly of common type, the European patent publication No.259 of Rath for example, install shown in the 163A2 for example.This device has the middle body of sheet diaphragm, and this sheet diaphragm is directly installed to be attached on the non-yielding prop.Successively, the elastic component of the block of this non-yielding prop by including flexible or rubber is connected on the main body of assembly, diaphragm can be tilted be complementary with the inclination with device.The U.S. Patent No. 4 of Huff, 918,383 have shown a kind of closely-related device, wherein the sheet spring that radially extends allows the vertical axis of non-yielding prop to move and prevents that simultaneously it from tilting, make and do not have slip or " misalignment " of contact projection on the pad, and further make whole diaphragm in horizontal plane, to move slightly, so that in order to remove oxide on surface and to make each contact " wiping " by their pads separately from these pads.

Yet, with regard to two aspects of these devices, because manufacturing tolerance is arranged, some contact projection seems to be in recessed position with respect to their adjacent protrusion, and these recessed projectioies will not have enough chances to engage with their pad, because they will be pulled away from their pad under their effect of adjacent protrusion on the non-yielding prop.Moreover even possess " wiping " motion in the Huff mode, they will tend to frictionally cling device when each contact is implemented wiping motion, and promptly Zhuan Zhi each pad has the trend that moves with each contact to cause contact motion inefficacy.No matter any wiping action, its actual generation all depends on pad and how far can move, and successively, this depends on the degree of side direction play again, and play is owing to there is the result of normal tolerance between each load-bearing surface of measuring head and chuck.Therefore the Membrane probing assembly of this form can not guarantee reliable electrical connection the between each contact and the pad.

The Membrane probing assembly of second kind of common type is the European patent publication No.304 of Barsotti, the example that installs shown in the 868A2.This device provides flexible backrest for central authorities or the contact carrying the part of flexible membrane.In the patent of Barsotti, diaphragm is directly propped up by elastic component and leans on, and successively, this elastic component is propped up by non-yielding prop and leans on, so can adapt to less height change between each contact or each pad.Also possibility application of positive pressure air, negative pressure air, liquid or unbacked elastomer come to lean on for diaphragm provides flexible propping up.As U.S. Patent No. 4,649,339, the U.S. Patent No. 4,636,772 of Ardezzone, the Reed of Gangroth, in people's such as people's such as Jr. U.S. Patent No. 3,596,228 and Okubo the U.S. Patent No. 5,134,365 shown in respectively.Yet these devices that substitute are provided with between test contact and device pad and give enough pressure so that penetrate the oxide that is created on the gasket surface reliably.

In the Membrane probing assembly of this second kind of form, as pointed in the Okubo patent, each contact can be constrained to along z axis and move, so that prevent slip between contact and pad between joint aging time and the misalignment that causes thereof.So in the Barsotti patent, the non-yielding prop that is positioned at below the elastic component is fixed on the correct position, though to the motion of Z axle, also can be by the U.S. Patent No. 4,980 of Huff, the mode shown in 637 is installed non-yielding prop.Yet, the design of this form may produce the pad damage, because between each contact and device, generally a certain amount of inclination can occur, and those angled ground the contact of close device will produce much higher contact pressure usually than the contact of those angled ground separating devices.The European patent publication No.230 of Garretson, relevant assembly shown in the 348A2 has revealed identical problem, although in the Garretson device, the characteristics of elastic component are: enter extruding with their pad and order about each contact when engaging and be displaced sideways when those contacts are placed in.Also have another relevant assembly to be shown in the U.S. Patent No. 4,975,638 of Evans, it has been used the supporting that is rotatably mounted and has propped up by elastic component, so that adapt to the inclination between each contact and the device.Yet the Evans device runs into the friction of having described and pastes problem, and its degree reaches the pad of device when supporting is pivoted and caused that each contact is displaced sideways as having clung contact.

The Membrane probing assembly of other common type is shown among people's such as people's such as the U.S. Patent No. 5,395,253, Barsotti of Crumly U.S. Patent No. 5,059,898 and Evans the U.S. Patent No. 4,975,638.In the patent of Crumly, applied spring makes the core that can expand diaphragm flexibly be biased to the state of expansion fully.When each contact engaged with their pads separately, the core of expansion was retracted to the part relaxation state against spring, so that spur each contact towards the diaphragm center on radially wiping direction.In the patent of Barsotti, every row's contact is by the overhang bracket of separately L type arm, so when each contact in a row engaged with their pads separately, corresponding arm is crooked up also to cause bank of contacts side direction wiping side by side by their pads separately.Yet, in two patents of Crumly and Barsotti, in the moment that engages, if between each contact and device, any inclination occurs, this inclination will cause angled ground each contact of the most approaching device than those angledly further from each contact wiping more of installing.Moreover short contact is had an opportunity with before they pads separately engage at them, because the control wiping action of their adjacent contact, short contact will be forced on their wiping direction mobile.Particularly, the shortcoming that the Crumly device also has is, near relatively more close peripheral those contacts wiping less of each contact at diaphragm center, so wiping efficient changes with contact position.

In people's such as Evans U.S. Patent No. 5,355,079, each contact constitutes a spring metal and refers to, and each refers to that the mode that is mounted to cantilever becomes the extension of predetermined angular ground to leave following diaphragm with respect to diaphragm.In the U.S. Patent No. 5,521,518 of Higgins, introduced similar structure.Yet, allow these refer to that it is difficult initially being positioned to make them to end at common plane, be like this during high density patterns if desired particularly.Moreover these refer to be bent away from easily its position and are difficult for their initial position of replication again between the operating period.Therefore, some refers to tend to the finger touching prior to other, and often different for different finger wiping pressure and distance.And, in the Evans patent, do not have yet suitable at least mechanism with allow to refer to and pad between the inclination of less degree is arranged.Though the Evans suggestion makes each surperficial roughening that refers to improve the quality that is electrically connected, this roughening can cause gasket surface undue wear and damage.The shortcoming that the other contact that shows in two patents of Evans and Higgins refers to is that after lacking " touching " or working cycles of number of times relatively, because repeated flex and stressed, fatigue and inefficacy can take place this finger.

With reference to figure 1, the Cascade Microtech Inc. in Beaverton city, Oregon state has developed a kind of measuring head 40 that is used to install membrane probing system 42.In order to measure the electrical property in the special little circuit wafer zone 44 that is included on the silicon wafer 46, the high-speed digital line 48 and/or the shielded transmission line 50 of measuring head are connected in the I/O port of check meter by suitable CA cable assembly, and the chuck 51 that is supporting wafer moves so that carry the pad in the zone of little circuit wafer in mutually perpendicular X, Y, Z direction and pushes with each contact on the following contact portion that is included in the Membrane probing assembly and engage.

Measuring head 40 includes the test board 52 that is furnished with data/

signal line

48 and 50 on it.With reference to figure 2～3, Membrane probing assembly 42 includes the supporting member 54 that is formed by the incompressible material such as hard polymer.This element removably is connected the upside of test board with 4 hex bolts 56 and corresponding nut 58 (each bolt passes the linking arm separately 60 of supporting member, and by element 62 clamping force of bolt being distributed equably of separating reaches the whole dorsal part of supporting member).According to this dismountable connection, different test suites has different contact structures, tests different device if desired, and contact structures can be replaced mutually apace.

With reference to figure 3～4, supporting member 54 includes the back bottom parts 64 that fuses with linking arm 60.Also comprise the preceding supporting or the plug 66 that outwards protrude out from smooth bottom parts on the supporting member 54.Supporting has towards the inclined side 68 of smooth area supported 70 convergences, so that preceding supporting has the shape of truncated pyramid before this.Also with reference to figure 2, flexible membrane assembly 72 is included in alignment pin 74 on the bottom parts in utilization and is installed in the supporting after aiming at.This flexible membrane assembly is formed by one or more layers insulating trip or other Kapton, all KAPTON that is sold by E.I.Du Pont de Nemours in this way of this insulating trip ^TM, and compliant conductive layer or band be placed in these the layer between or it on formation data/signal line 76.

When supporting member 54 is installed in the upside of test board 52 as shown in Figure 3, the central opening 78 that passes on the test board is protruded in preceding supporting 66, so that each contact on the middle section 80 that is arranged in the flexible membrane assembly is appeared on the correct position that engages with the pad extruding of device when checking.With reference to figure 2, diaphragm unit comprises the arm section 82 of radially extending, and arm section 82 is separated by aduncate edge 84, and edge 84 makes assembly have the shape of armory cross (formee cross), and these arm sections are extended along hypotenuse 68 in the mode that tilts, and remove any setting composition around pad thus.A series of contact pins 86 are terminals of data/signal line 76, during with convenient mounting support element, these pads engage on circuit with the corresponding terminal pad that is located at the test board upside, make the data/signal line 48 on the test board be connected in each contact of middle section on circuit.

The characteristics of test suite 42 are performances that a large amount of number of times in footpath of its intensive a little layout of test in some way contact the contact pins of circulation, this mode provides reliable the electrical connection usually between contact and pad in each circulation, although accumulation has oxide on the pad.This performance is the function of the structure and their mode that is connected to each other of supporting member 54, flexible membrane assembly 72.Especially, diaphragm unit is to be configured to and to be connected in supporting member like this, promptly is brought into when these pads contact when contact, preferably laterally smears or the pad that nuzzles up under local control mode at the contact on the diaphragm unit.Described the structure of the preferred film chip module 72a that the preferred means that is used for producing this wiping action and Fig. 6 and Fig. 7 a-7b describe best and be connected to each other.

Fig. 6 has shown the zoomed-in view of the middle section 80a of diaphragm unit 72a.In this embodiment, each contact 88 is arranged to square pattern, is suitable for combining with the square structure of pad.Also with reference to figure 7a, its expression is along the cutaway view of the intercepting of the 7a-7a line among Fig. 6, and each contact comprises thick relatively buckstay 90, has made rigidity contact projection 92 at the one end.Contact projection comprises the contact portion 93 on it, and contact portion 93 comprises the fritter rhodium of welding on contact projection.Use to electroplate and to ask, each beam forms with the end stack ways of connecting with the conduction spike part 76a of flexibility, connects so that form thus.This conduction spike part that links with plane, back conductive layer 94 provides the controlled impedance data/signal line to contact effectively, because its size is to use photoetching process to set up.The top opening that preferably includes of back plane layer is to help for example gas discharging during manufacture.

By the elastic layer 98 that inserts diaphragm unit and smooth area supported 70 are connected to each other, this elastic layer 98 coextends with area supported and available silicon resin rubber compound is made, all ELMER ' the S STICK-ALL that is made by Borden company in this way of this compound ^TMOr the Sylgard 182 that makes by DowCorning company.This compound can use under paste-like easily, and it hardens when ready.As previously mentioned, smooth area supported is made by incompressible material and preferably hard electrical insulator, such as polysulfones or glass.

According to structure described above, when a contact 88 is brought into when engaging with corresponding pad 100 extruding, shown in Fig. 7 b, the elastic restoring force that the eccentric force that produces on buckstay 90 and protruding 92 structures causes beam to overcome being produced by elastomeric pad 98 is rotated or is tilted.The forward part 102 that the orientation of this banking motion is confined to beam is towards the displacement of smooth area supported 70 displacement greater than the rear section 104 of same beam.Consequently, order about contact and make the side direction wiping motion, as shown in Fig. 7 b, represent contact beginning and end position on pad with dotted line and solid line respectively by pad.In this mode, the insulation oxide that is accumulated on each pad is removed, to guarantee the abundant electrical connection of contact to pad.

Fig. 8 represents contact 88 and pad 100 at initial engagement or touching relative position constantly with dashed line view, and represents that with real diagram these components identical are directly towards the relative position after pad " surmounts " distance 106 on the vertical direction of smooth area supported 70.As shown in the figure, the distance 108 of side direction wiping motion directly depends on the vertical deflection of contact 88, or depends on the cross over distance 106 that pad 100 moves equivalently.Therefore, because the cross over distance of each contact on middle section 80a will be identical (because of the variation of contact height creates a difference) basically, the side direction wiping motion distance of each contact on middle section will be uniformly basically, and especially not be subjected to the influence of the relative position of each contact on middle section.

Because elastic layer 98 is propped up by incompressible area supported 70 to lean on, so elastic layer keeps the pressure of contact to pad during applying restoring force on each inclined beams 90 and making each contact 93 wipe examination thus.Meanwhile, elastic layer can adapt to some height change between each contact.So, with reference to figure 9a, when relatively short contact 88a between tightly adjacent a pair of higher contact 88b and these higher contacts be brought into its corresponding pad when engaging, so, as shown in Fig. 9 b, pad further do some surmount after, the distortion of elastic layer allows shorter contact to be brought into its pad to engage.Should note, in this example, the tilting action of each contact is controlled partly, and especially bigger contact can tilt independently with respect to less contact, is not done lateral movement so that less contact does not order about before on its pad in its practical touch.

With reference to Figure 10 and 11, the electroplating technology of constructing this girder construction includes as shown in Figure 8 with anticipating, limits the incompressible material 68 of area supported 70, with the backing material that is connected thereon such as elastic layer 98.Use the crooked circuit constructing technology, generate the pattern of compliant conductive spike part 76a then on the sacrifice property substrate.Secondly, form polyimide layer 77 patterns, to cover sacrifice substrate except the desired location of beam 90 on spike part 76a part and the whole surface of spike part 76a.Beam 90 is electroplated in the opening of polyimide layer 77 then.After this, the pattern that generates photoresist layer 79 on two surfaces of polyimides 77 and beam 90 is with the opening of the desired location that stays contact projection 92.Electroplate in the opening of contact projection 92 on photoresist layer 79 then.Remove photoresist layer 79 and make thicker photoresist layer 81 pattern to cover the exposed surface except that contact portion 93 desired locations.Electroplate in the opening of contact portion 93 on photoresist layer 81 then.Remove photoresist layer 81 then.Remove sacrifice property substrate layer and each remaining layer is connected on the elastic layer 98.As illustrated more accurately among Figure 12, final beam 90, contact projection 92 and contact portion 93 provide the independently inclination and the wiping function of device.

Unfortunately, above-mentioned constructing technology causes structure to have many undesirable characteristics.

First, some beams 90, contact projection 92 and contact portion 93 (they each can be regarded a device as) are closer to each other, cause local current densities different in the electroplating bath, successively, this causes the difference on the height of many beams 90, contact projection 92 and contact portion 93 again.Also have, " at random " in the different densities of electroplating bath intermediate ion and the electroplating bath changes the difference on the height that also causes many beams 90, contact projection 92 and contact portion 93.The differing heights of many beams 90, contact projection 92 and contact portion 93 is three composition aspects of the total height of many devices.Therefore, many devices will have and the remarkable different height of other device.Membrane probing needs with variset height have such as all devices of fruit required bigger pressure of pressure when having equal total height, fully contact with verifying attachment to guarantee all contact portions 93.For the density film built-in testing, such as having 2000 or more device in small size, the accumulative effect of the additonal pressure that each device is required may surpass the total force that measuring head and testing station allow.This excess pressure also can cause the crooked of testing station, measuring head and/or Membrane probing assembly and destroy.In addition, because make the pressure of the required increase of the good contact of the device with minimum altitude, may make the pad on the device Damage Survey device with maximum height.

The second, the performance that reduces the pitch (at interval) between the device is subjected to the restriction of electroplating technology to " ramp " effect at the edge of polyimides 77 and photoresist layer 79 and 81." ramp " effect is restive and cause the wide variety of beam 90, contact projection 92 and contact portion 93.If the height of beam 90, contact projection 92 or contact portion 93 increases, then " ramp " effect increases usually, so the width of each several part increases.The width increase of a part generally causes the general arrangement broad, and this has increased the minimum interval between the contact portion 93 successively.On the other hand, the height of beam 90, contact projection 92 or contact portion 93 reduces generally to make the width of " ramp " effect to reduce, and this has reduced the minimum interval between the contact portion 93 successively.Yet if contact portion 93 reduces fully with respect to the height of respective beam 90, in use the rearward end of beam 90 can tilt fully and at an acceptable position exposure test device, promptly disengage pad.

The 3rd, be difficult to second metal level directly is plated in the top of the first metal layer, such as contact portion 93 is plated on the contact projection 92, particularly be like this when application of nickel.For combining between contact projection 92 and the contact portion 93 is provided, the interface crystal grain layer of having used such as copper or gold is connected to each other with improvement.Unfortunately, because lower complete (sheer) intensity of interface layer, this interface crystal grain layer has reduced the lateral strength of device.

The 4th, above heterogeneous surface, to use the photoresist layer and often have half conformal nature, this character causes the in uneven thickness of photo anti-corrosion agent material itself.With reference to Figure 13, the photoresist layer 79 (and 81) of the rising part of beam 90 top is often thicker than the photoresist layer 79 above the lower part of polyimides 77 (and 81).In addition, the thickness of photoresist layer 79 (and 81) often changes with the density of beam 90.Therefore, in Membrane probing zone with device that comparatively dense distributes, the average thickness specific density of its photoresist layer 79 (and 81) the thicker of rarer device that distribute.During the exposure and etch processes of photoresist layer 79 (and 81), the duration of technology is depended on the thickness of photoresist 79 (or 81).Because the photoresist variable thickness is difficult to handle well photoresist so that uniform opening to be provided.Moreover the thinner region of photoresist layer 79 (or 81) tends to overexposure, causes opening size to change.Also have, the thickness of photoresist layer 79 (or 81) is big more, and its varied in thickness is just big more.Therefore, there are many handling problems in the application of photoresist.

The 5th, independently registration process needs, and is aligned in the beam 90 on the spike part 76a, is aligned in the contact projection 92 on the beam 90, and is aligned in the contact portion 93 on the contact projection 92.Each registration process all has inherent variation, and this variation must be calculated when determining every portion size.The minimum dimension of contact portion 93 is mainly limited by the maximum allowable current density in lateral strength requirement and this part.Calculate the tolerance in aiming at, define the minimum dimension of contact projection 92 successively again, make contact portion 93 be configured in definitely on the contact projection 92.Consider the tolerance in contact portion 93 and the calculating aligning, the minimum dimension of contact projection 92 defines the minimum dimension of beam 90, makes contact projection 92 be configured in definitely on the beam 90.Therefore, contact projection 92 defines the plant bulk of minimum with the tolerance sum of contact portion 93 with the minimum dimension of contact portion 93, and defines the minimum pitch between each contact pins thus.

Therefore, desirable Membrane probing constructing technology and structure are summed up as, more uniform device height, the interval between each device that reduces, maximized lateral strength, desirable geometry, and appropriate aligning.

The general introduction of invention

The present invention overcomes the aforesaid drawbacks of prior art by a kind of substrate that preferably is made of ductile material is provided.A kind of instrument with the required shape of resulting device is used for contacting with contact pins on the verifying attachment, and this instrument is brought into substrate and contacts.This instrument preferably is configured to by the material harder than substrate, so that can easily form depression therein.A kind of non-conductive (insulation) layer that preferably generates pattern is supported by substrate.Conductive material is placed in and preferably makes it complanation within the depression then to remove fifth wheel and smooth general surface is provided from the top surface of non-conductive layer.On non-conductive layer and conductive material, form spike part pattern.Be preferably in the pattern that forms polyimide layer on the whole surface then.Remove substrate with any suitable technology then.

To more easily understand aforementioned and other purpose, characteristics and advantage of the present invention according to following detailed description of the present invention and connection with figures.

The brief description of some views of accompanying drawing

Fig. 1 is the perspective view of Membrane probing assembly and wafer, and this test suite is fixed by bolts on the measuring head, this wafer supporting on the correct position of chuck to use this module testing.

Fig. 2 is the bottom front view of each several part of test suite of presentation graphs 1 and the partial view of test board, the each several part of the side of Fig. 1 examination assembly comprises supporting member and flexible diaphragm unit, and test board has the data/signal line that is connected with respective lines on the diaphragm unit.

Fig. 3 is the side view of the Membrane probing assembly among Fig. 1, and a part of wherein having removed diaphragm unit is to expose the built-in part of supporting member.

Fig. 4 is the top view of typical supporting member.

Fig. 5 a～5b is the side view of signal, is illustrated in supporting member and diaphragm unit are how to realize being complementary with the orientation with device in the check.

Fig. 6 is the amplification vertical view of middle section of structure of the diaphragm unit of Fig. 2.

Fig. 7 a～7b is the cutaway view that intercepts along the 7a among Fig. 6～7a line, and at first the contact before the expression touching then is illustrated in touching and wiping and moves through its pad separately same contact afterwards.

Fig. 8 is the side view of signal, is represented by dotted lines the contact in initial touching Fig. 7 a～7b constantly, and represents that with solid line pad further vertically surmounts same contact afterwards.

The distortion that Fig. 9 a and 9b represent elastic layer enters with its pad and contacts to drive contact.

Figure 10 is the longitudinal sectional view of the device of Fig. 8.

Figure 11 is the cross-sectional view of the device of Fig. 8.

Figure 12 is Figure 10 and the more accurate schematic diagram of 11 shown devices.

Figure 13 is the detailed view of device shown in Figure 11, the uneven layer that expression causes during handling.

Figure 14 is the schematic diagram of substrate.

Figure 15 is the schematic diagram of the one exemplary embodiment of instrument of the present invention, and its schematic diagram of the one exemplary embodiment of a system work holdup tool particularly.

Figure 16 is that the instrument of expression Figure 15 enters the schematic diagram that contacts with the substrate of Figure 14.

Figure 17 be Figure 15 instrument with the substrate of Figure 14 enter contact after the schematic diagram of this substrate.

Figure 18 is the cutaway view of the substrate of Figure 14, and this substrate has supporting polyimide layer thereon.

Figure 19 is instrument and the Z-axle retainer schematic diagram together of Figure 16.

Figure 20 is the cutaway view of the substrate of Figure 14, and this substrate has the spike part, be in conductive material in the depression and additional polyimide layer thereon.

Figure 21 is the schematic representation of apparatus of Figure 20, is in upturned position, has removed substrate.

Figure 22 is the cutaway view of disconnection of the contact portion of Figure 21.

Figure 23 is the schematic views of a kind of layout of expression device of the present invention.

Figure 24 is the explanatory view of the oxide skin(coating) of expression contact of traditional contact portion and solder bump.

Figure 25 is the plane that has another device of elongated part of detecting.

Figure 26 is the side view of device of having of Figure 25 of elongated part of detecting.

Figure 27 is the schematic diagram of solder bump, has the vestige that the device by Figure 25 and 26 causes on this projection.

Figure 28 is the schematic diagram of another testing arrangement that substitutes.

Figure 29 is the schematic diagram that is applicable to the other testing arrangement that substitutes of solder bump.

Figure 30 is a side view of using the real Kelvin connector of device of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED

At present the constructing technology of using that is used for Membrane probing relates to from smooth rigid substrate and beginning to the technology of making supporting extra play thereon.In order to reduce pitch and the inhomogeneity device with raising to be provided, need become increasingly complex and expensive treatment technology.Directly contrast with the prior art of each layer of structure, the prior art is constructed each layer according to " inversion " mode on support substrate, the present inventor has realized by using proper tools pressure-sizing to go out substrate to generate required beam, contact projection and contact portion.Yu Xia each layer is configured on the beam " top-down " then.Substrate itself is removed afterwards.

With reference to Figure 14, substrate 200 preferably is configured to by ductile material, and all aluminium in this way of this ductile material, copper, lead, indium, brass, gold, silver, platinum or tantalum, its thickness are preferably between 10 mils and 1/8 inch.The top surface 202 of substrate 200 preferably smooth and be polished to certain optical clarity to improve outward appearance, as described later.

With reference to Figure 15, instrument particularly " system nest " instrument 210 is configured to have head 212, this head 212 have the required shape of resulting device with verifying attachment on contact pins contact.System work holdup tool 210 include with make nest machine (not shown) is connected protrude out bar 214.Instrument 210 is by the supporting of system nest machine, and this head 212 is oriented to enter with the top surface 202 of substrate 200 and contacts.Instrument 210 is preferably by be configured to, make easily to constitute recess on substrate than substrate 200 hard materials.The material that is fit to the instrument of doing 210 for example is tool steel, carbide alloy, chromium and diamond.Preferred system nest machine is the testing station with accurate X, Y and the axial control of Z.Should be understood that any other suitable system nest machine can be used equally.With reference to Figure 16, instrument 210 is squeezed to enter with the top surface 202 of substrate 200 and contacts, in case instrument move apart from substrate 200, the depression 216 of result with regard to causing a shape with instrument 210 to be complementary, as shown in Figure 17.Instrument 210 is used to generate a plurality of depressions 216 that are complementary with required figure on substrate 200, and this required pattern is the pattern shown in Fig. 6 for example.On the contrary, instrument 210 can be maintained fixed and substrate 200 can move top surface 202 until substrate along the Z direction is squeezed to enter with instrument 210 and contacts, in case instrument 210 leaves substrate 200, the result just causes the identical depression 216 that is complementary with the shape of instrument 210, as shown in Figure 17.

With reference to Figure 18, polyimide layer 220 constitutes pattern around depression 216.It should be understood that and also can similarly use any other suitable insulation layer or non-conductive layer.In the processing of the pattern that generates polyimide layer 220, during the exposure of polyimide layer 220 and etch processes, remove polyimides 216 and have any problem slightly from caving in.Relatively dark and when having precipitous inclined side when depression 216, this point is actual especially.Another kind method is, polyimide layer 220 can generate patterns at the top surface 202 of substrate 200, and opening is positioned at and wherein needs to cave in 216 parts.Afterwards, application tool 210 generates depression 216 by opening on substrate 200, and this opening is located on the polyimide layer 220.This substitute technology has been eliminated the difficult process of removing polyimide layer 220 fully 216 from caving in.

For making polyimide layer 220 exposures make mask is expensive, and the tolerance that this polyimide layer 220 has is be used to cave in 216 opening accurately to aim at.Instrument 210 combines with system nest machine can aim at the physical location of an opening, and this has caused with inexpensive and coarse a little mask relatively polyimide layer 220 exposures and etching.The present inventor realizes, the mask regional area, and consequent opening tends to aim at relatively well into system nest purpose.The zone of equally, apart mask often can not aimed at for system nest purpose relatively well.Therefore, use accurate system nest machine on substrate 200, automatically make nest with have each other from the pattern of expection of many depressions 216 be complementary, this will cause making work holdup tool can not accurately aim at opening, this opening is leaving the location of initial alignment point.Aim at the precision open skill in order to improve, the present inventor has realized that system nest machine can aim at the actual aperture on the polyimide layer 220 of different off-site location, thereby makes each regional area relatively accurately be aimed at, and totally to departing from a little.In this mode, can use relatively inexpensive mask.

System nest machine preferably includes accurate Z axle motion, makes the deep equality of each depression, or equal substantially.With reference to Figure 19,, then can use alternative system work holdup tool 240 with built-in Z axle retainer 242 if can not obtain enough accurate Z axle motion.This Z axle retainer 242 is to protrude out bar, and this protrudes out bar and 244 stretches out from the head, and head 244 can stop on the top surface of polyimides 220 or on the top surface 202 of substrate 200.This Z axle retainer 242 is with respect to head 244 location, thereby can obtain the suitable degree of depth, and this has considered whether before using system work holdup tool 240 polyimide layer 220 is made into the situation of pattern in advance.

With reference to Figure 20, conductive material 250 be electroplated onto polyimides 220 and substrate 200 above, thus with conductive material 250 fill up the depression 216, all nickel in this way of this conductive material and rhodium.Should be appreciated that any other suitable technique all can be used to conductive material is inserted in the depression 216.Conductive material 250 is preferably polished so that remove fifth wheel and smooth all surfaces is provided from the top surface of polyimide layer 220 then.Preferred glossing is a chemical mechanical planarization

technology.At polyimide layer

220 and 252 pattern of formation spike part spare above the conductive material 250.Spike part 252 is preferably such as copper, aluminium or golden good conductor.On whole surface, form the pattern of polyimide layer 254 then.Also can form additional metals layer and non-conductive layer.Utilize any suitable technology to remove substrate 200 then, such as using hydrochloric acid (HCL 15%) or sulfuric acid (H ₂SO ₄) etch process.Hydrochloric acid and sulfuric acid neither do not react with conductive material 250 such as nickel or rhodium with polyimide layer 220 yet.Should be appreciated that polyimide layer 254 can replace with any suitable insulation body or non-conductive layer.

With reference to Figure 21, the contact portion 260 of resulting device is preferably selected to such an extent that have low contact resistance, so that can form good being electrically connected with verifying attachment.And nickel has low relatively contact resistance, rhodium even have than the lower contact resistance of nickel and more wear-resisting than nickel.Therefore, depression 216 preferably covers with the rhodium layer.Use common treatment technology, the thickness limits of rhodium is at about 5 microns.Resulting device and particularly contact portion 260 include the skin of rhodium, and it is filled out with remaining conductive material or non-conductive filler all nickel in this way of this conductive material then.Do not need conductive material is filled out in whole depression.

Above-mentioned 'top-down' construction process is compared with " inversion " treatment technology of each layer of structure on support substrate many advantages is provided.These advantages also allow can be with the characteristics constructing apparatus that improves.

The first, the height of resulting device is provided with restriction, this resulting device has applied the restriction that photoresist is handled in advance.Structure has the performance of the device of any desired height also have been broken away from by attempting to electroplate the restriction that is applied in the high narrow opening of photoresist, and this plating is difficult.

The second, the rise of the contact portion 260 of device is extremely even, because it is only determined by tool processes technology, and this technology is mechanical in essence.Eliminated the different local current densities of electroplating bath, the different ions density in the electroplating bath and " at random " in electroplating bath variation influence to the overall shape and the height of resulting device.Owing to the basic of device risen uniformly, it is less to make device and verifying attachment fully contact required power, the possibility that this has reduced testing station, measuring head and/or the bending of Membrane probing assembly successively and has broken.Also have, device basic risen uniformly and reduced because excess pressure and the possibility of contact pins on the Damage Survey device.

The 3rd, the contact portion 260 of device is firmer, because this device is to be configured to by the material of single homogeneity during the primary depositing technology of each layer that need not to demarcate, as previous required in the Combined Processing step.This allows the size of contact portion to be decreased to a limit, and this limit is the minimum limit of power fully of each layer of the limit of the maximum current density that wherein allowed the inspection period rather than boundary.

The 4th, the shape of resulting device is customized to tests different materials effectively.The shape of device can have the precipitous Sidewall angles such as 85 °, and mechanical strength, stability and globality still are provided.The sidewall of steep nitre allows the narrower device of structure, and this device allows to be used for the bigger device density that the more and more intensive contact pins on verifying attachment is arranged.In addition, the angle of sidewall does not rely on the crystal structure of (for example being independent of) substrate.

The 5th, know the shape of contact portion clearly, and it is uniformly between each device, this allows the contact pins even contact of it and checkout gear.

The 6th, being aligned between each device of the different piece of resulting device is accurately uniformly, because each device is to use identical tool processes technology to be configured to.Because the leeway that the bottom of each device (beam has contact projection) with respect to the accurate aligning of contact portion, does not just need to provide additional adapts in the photoresist technology and electroplating technology in intrinsic processing variation.Also have, eliminated " mushroom growth " effect of electroplating technology, this has also reduced to install required size.The aligning of different device 300 is variable to be reduced and actual elimination can reach the pitch that significantly reduces, and it is suitable for the contact pins of the density with increase on the verifying attachment.

The 7th, the shape of resulting device can be that special shape is to provide best mechanical performance.As described in the background parts, for wiping function is provided, device should have beam and the bulge-structure that tilts at contact.Device 300 inclined surfaces 304 that can include between its afterbody 302 and contact portion 260.In order to improve along the intensity of the length of device 300 part inclined surface 304 is set, this allows afterbody 302 thinner than its head 306.Be tending towards reducing on the total length of device 300 at the twisting resistance that acts on during the tilting procedure of device 300 on the device 300, device 300 has correspondingly thin material, and this material limits according to inclined surface 304.Because the material that thin afterbody 302 reaches near afterbody 302, if excessive inclination takes place, what 302 pairs of verifying attachments of afterbody of device 300 exerted an influence may become less.The improvement shape of device 300 has also reduced the amount of required metal material.

The 8th, used the image of " inspection " camera, so that determine the exact position of device 300 with respect to the contact pins on the verifying attachment with the lower part of acquisition diaphragm gauge head.Use " inspection " photograph function and realize the automatic aligning of diaphragm device, so that can finish automatic gauging with respect to contact pins.In order to obtain the image of the device 300 on the diaphragm gauge head, " inspection " flare-aircraft makes usually to use up and illuminates device 300.Unfortunately, traditional plane treatment technology causes on the beam, on the contact projection and the surface of the relatively flat on the contact portion, and on the orientation perpendicular to " inspection " camera, each flat surfaces is all light reflected back " inspection " camera.Cause some interference continually from the light of all surface reflected back " inspection " camera to the exact position of contact portion 260.The inclined surface 304 of device 300 tends to reflect away the incident light from " inspection " camera of arranging than the lowland, and contact portion 306 tends to incident light reflected back " inspection " camera than the lowland layout.Main light from contact portion 306 is back to " inspection " camera and causes the potential interference less to the exact position of contact portion.

The 9th, the initial burnishing result of the top surface 202 of substrate 200 produces the smooth lower surface that is complementary with the polyimide layer 220 that generates pattern on substrate 200.After etching away or otherwise removing substrate 200, the lower surface of polyimide layer 220 is that smooth and final polyimide layer 220 optically is transparent usually.Therefore, spike part and space between the metallized device 300 are relative printing opacities, so that the operator of device location can easily understand thoroughly the device of spike part between installing with each.This helps the operator to carry out the manual location of diaphragm gauge head on device, will be covered otherwise install.In addition, the pyramidal shape of device 300 makes the operator more easily determine the exact position of contact portion with respect to the contact pins on the verifying attachment, and they had before been covered by wide beam structure (with respect to contact portion).

The tenth, with reference to Figure 22, the contact portion 260 of device preferably is configured with the outer surface 340 of rhodium, generally can be plating to only approximate 5 micron thickness effectively.The plating technic of rhodium is half conformal, so final layer approximate 5 micron thickness on the direction vertical with lateral surface 352 and 354.The rhodium 340 that the angle Selection of the width at the top 350 of contact portion and the side 352 of

instrument

210 and 354 becomes to make to be plated on two

sides

352 and 354 preferably is joined together to form V-type.The remainder of device is nickel preferably.And the thickness of rhodium 340 only is 5 microns in vertical direction, and the thickness of rhodium 340 on the vertical direction at the top 350 of device is greater than 5 microns.Therefore, can be during using at the top this contact portions of 350 common vertical direction wearing and tearing will only plate with the rhodium continuity of 5 micron thickness such as the fruit top and use for more time.

The 11, the structure of contact portion 260 may be selected to the wiping effect that provided a description on the contact pins of verifying attachment.Especially, instrument can include the rough surface pattern on the corresponding contact portion so that provide uniform structure for all devices.

The 13, using constructing technology of the present invention, to construct each device be fast relatively, because reduced the quantity of treatment step, causes saving significantly cost.

Above-mentioned constructing technology also provides some advantages that relate to the device shape, otherwise this device will be difficult to structure, if not impossible words.

The first, if do not need wiping action, instrument can be provided with any shape of wanting, such as simple projection.

The second, and be that a part of metal is opposite by the bigger situation that contact projection supported, provide superior mechanical support up to the inclination supporting side of the verifying attachment of contact portion 260 for contact portion 260.Have this supporting, can make contact portion become littler and can not emit it will be from installing risk separately from inclined side.When device tilts penetrating when being accumulated in the lip-deep oxide of contact pins, less contact portion has been improved and the contacting of the contact pins of verifying attachment.In addition, all the other ones of afterbody 302 comparable device of device are thinner significantly, this reduced when device tilts in the contact pins influence of 302 pairs of checkout gears of inspection period afterbody may.

The 3rd, change by the pivot of the contact portion applied pressure that installs by modifier, the contact portion of this device is given the predetermined pressure that is applied by measuring head.The pivot of device can be selected with respect to the position/height of device by the length and the contact portion of selecting arrangement.Therefore, if desired, can selection pressure so that be complementary with the characteristic of two kinds of different contact pins.

The 4th, with reference to Figure 23, the triangle of device trace creates conditions for the height of devices lateral stability, and allows to reduce the respectively pitch between the device.For many contact pins of verifying attachment, the contact portion 403 of the device layout that preferably is arranged in a straight line.The gable of device is arranged in interchangeable relative direction.

The 5th, the performance of constructing each contact portion makes device that wiping action is provided and the lower surface that installs needs small motion, and this each contact portion raises from the lower surface of device, and the uniformity of holding device height and structural strength aspect still.The small movements of lower surface of device makes the inspection period that good electrical contact be arranged, and has reduced the stress on each layer below the lower surface of device.Therefore, polyimide layer and the cracked possibility of conduction spike part have been reduced.

When solder bump on the testing wafer or the oxide skin(coating) on the solder ball, this wafer will be used " flip-chip " wrapper technology, this solder bump or solder ball are such as the solder bump on the printed circuit board (PCB), and the oxide skin(coating) that produces on this circuit board is difficult to penetrate effectively.With reference to Figure 24, when traditional contact portion of diaphragm gauge head touched solder bump, oxide 285 tended to be pressed in the solder bump 287 with contact portion 289, causes bad being connected to each other.When on solder bump, using traditional pin type gauge head, this syringe needle tends on solder bump to slide, to be bent to the solder bump lower interior, peels off fragment on fragment, the surface at verifying attachment and cleaning pin type gauge head is time-consuming and dull collecting on the syringe needle.Moreover the pin type gauge head stays test vestige heterogeneous on solder bump.When the solder bump Test Application was on flip-chip, the test vestige of staying the top of solder bump tended to hold back solder flux (flux) wherein, and solder flux tends to blast when being heated, and this deterioration or otherwise destroy is connected to each other.With reference to Figure 25 and 26, shown a kind of improved apparatus structure, be applicable to the test solder bump.The top of device includes a pair of side that tilts 291 and 293 precipitously, such as become 15 ° of angles, the side that preferably polish this side with vertical line.Inclined side 291 and 293 is preferably formed as sharp-pointed ridge 295 at its place, top.Side 291 and 293 angle are selected according to the coefficient of friction between the oxide on side and the solder bump, make that the oxide of covering surfaces is tending towards mainly 291 and 293 the surface slip along the side when device penetrates solder bump, perhaps otherwise cut off, rather than significantly appendix on the side.With reference to Figure 27, sharp-pointed basically ridge has also produced vestige (locating slot) after contact, the whole solder bump of this vestige extend past.Solder bump causes solder flux to be left away from the side of solder bump with the heating subsequently of solder flux, has avoided the possibility of blast thus.In addition, the final vestige of staying on the solder bump is uniformly in nature, and this allows the manufacturing of solder bump that final vestige is considered in their structure.Also have, the power that need be applied on the device is less, contacts because it tends to cut wear solder bump rather than push with solder bump.More smooth surface 405 prevents to cut too far solder ball (projection).

With reference to Figure 28,, can use cell structure shape pattern for the check solder bump provides bigger contact area.

With reference to Figure 29, a kind of alternative device includes a pair of

convex extension part

311 and 313, and they preferably are positioned at the end of arch 315.The diameter that interval between the

convex extension part

311 and 313 cans be compared to solder bump 317 to be detected most is little.Because this layout,

convex extension part

311 and 313 will be hit in the side of solder bump 317, can not stay vestige the top of solder bump 317 thus.Because vestige is on the side of solder bump 317, the solder flux of Ying Yonging may become and less be trapped within the vestige and less blast subsequently.In addition, if the aligning of device is provided with centering center on solder bump 317, then extremely may be that in

convex extension part

311 and 313 still knocks solder bump 317.

Previous device construction technology causes contact portion that this device includes quite big and be difficult to guarantee to aim at.With reference to Figure 30, rely on improved constructing technology, the present inventor has realized can be the diaphragm gauge head as " real " Kevlin connector that is connected in the contact pins on the verifying attachment.Their contact portions adjacent one another are of a pair of

device

351 and 353

usefulness

355 and 353 are aimed at.According to this layout, device can " application of force " and another device to be the Kelvin check arrange " sensing " part.Two

contact portions

355 and 357 all contact with same contact pins on the verifying attachment.The more labor of Kelvin connector is described in Fink, D.G., ed., Electronics Engineers ' Handbook, 1sted., McGraw-Hill Book Co., 1975, Sec.17-61, PP.17-25,17-26, " The Kelvin Double Bridge ", with U.S. Patent application series No.08/864, in 287, more than two fens data to be bonded to this paper for referencial use.

Should notice that each device will present above-mentioned any advantage, these devices are according to the present invention, construct according to the structure of technology, required purposes and the realization used.

Claims

1. a method of constructing the diaphragm gauge head comprises:

(a) provide substrate;

(b) in described substrate, generate depression;

(c) conductive material is inserted in the described depression;

(d) will conduct electricity the spike part is connected in described conductive material; And

(e) remove described substrate from described conductive material.