US20070114204A1

US20070114204A1 - Method for making guide panel for vertical probe card in batch

Info

Publication number: US20070114204A1
Application number: US11/512,185
Authority: US
Inventors: Chih-Yung Cheng; H. Fan; Chih-Chung Chen; Hsin-Hung Lin
Original assignee: MJC Probe Inc
Current assignee: MJC Probe Inc
Priority date: 2005-11-21
Filing date: 2006-08-30
Publication date: 2007-05-24
Also published as: TWI261933B; TW200721512A

Abstract

A method for making a guide panel for a vertical probe card in batch includes the steps of a) preparing a non-metal substrate, b) forming a shielding layer having a plurality of openings on the substrate, c) etching a part of the substrate corresponding to the openings of the shielding layer by an anisotropic etching so as to form bind holes with a predetermined depth on the substrate, d) grinding the substrate to open the blind holes by a back side thinning technology so as to form micro feed through holes on the substrate, and e) removing the shielding layer so as to obtain the desired guide panel.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a guide panel for use in a vertical probe card and more specifically, to a method for making the guide panel in batch.
2. Description of the Related Art
As shown in FIG. 1, a vertical probe card 1 for testing properties of an electronic component comprises multiple guide panels 2, which have respectively a plurality of micro feed through holes 3 for the insertion of vertical probe pins 4 respectively to guide movement of the inserted vertical probe pins 4 along an axial direction of the through holes 3 and to prohibit the inserted vertical probe pins 4 from sideway displacement, thereby achieving probing the circuits of electronic component 5 under test.
Various guide panels for vertical probe cards have been disclosed. Exemplars are seen in U.S. Pat. Nos. 6,417,684; 6,297,657B1 and 6,404,211. According to U.S. Pat. No. 6,417,684, entitled “Securement of test points in a test head”, a conventional precision processing technique is employed to drill micro feed through holes in a ceramic, engineering plastic, glass or semiconductor material one by one. According to this conventional processing technique, there is a limitation on the position precision of micro feed through holes and the pitch between micro feed through holes (micro feed through hole position error will be greater than 15 μm; micro feed through hole pitch will be greater than 25 μm). Further, the manufacturing cost will be relatively increased subject to the number of the micro feed through holes to be made. This method does not meet modem technology requirements. According to U.S. Pat. No. 6,297,657B1, entitled “Temperature compensated vertical pin probing device”, metal plus dielectric material or insulating material are used for making the guide panel, and a laser processing technique is employed to make micro feed through holes on guide panels. This method achieves a better precision than the aforesaid conventional drilling method. However, using this laser processing technique to make the designed micro feed through holes one after another is complicated. The manufacturing cost and time are relatively increased subject to the number of the micro feed through holes to be made. According to U.S. Pat. No. 6,404,211, entitled “Metal buckling beam probe”, multiple metal layers are stacked to form the designed guide panel, and etching technology is employed to make micro feed through holes (apertures) in the metal layers. However, because etching technology cannot make micro feed through holes of high depth-to-diameter ratio, multiple metal layers must be stacked so that micro feed through holes of desired depth can be obtained. This fabrication method is complicated. Further, much time is wasted in stacking metal layers. Further, it is difficult to control levelling of stacked metal layers.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is the primary objective of the present invention to provide a guide panel fabrication method, which is able to make guide panels in batch, thereby saving much manufacturing time and lowering much manufacturing cost.
It is another objective of the present invention to provide a guide panel fabrication method, which makes micro feed through holes on guide panels in a high precision.
It is still another objective of the present invention to provide a guide panel fabrication method, which can greatly reduce the diameter of the micro feed through holes.
It is still another objective of the present invention to provide a guide panel fabrication method, which can greatly reduce the pitch between each two adjacent micro feed through holes.
It is still another object of the present invention to provide a guide panel fabrication method, which is practical to make big area guide panels for vertical probe card.
It is still another object of the present invention to provide a guide panel fabrication method, which is practical for making temperature compensated guide panels for vertical probe card.
To achieve these objectives of the present invention, the method for making guide panel for vertical probe card in batch comprises the steps of: a) preparing a non-metal substrate, b) depositing an etching masking layer on the substrate, c) forming a shielding layer having openings of a predetermined pattern on the etching masking layer, d) etching a part of the etching masking layer corresponding to the openings of the shielding layer by a reactive ion etching so as to form apertures on the etching masking layer corresponding to the openings of the shielding layer, e) removing the shielding layer, f) etching a part of the substrate corresponding to the apertures by an anisotropic etching so as to form micro feed through holes on the substrate corresponding to the apertures, and g) removing the etching masking layer so as to obtain the desired guide panel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing showing a status of use of a conventional vertical probe card.
FIGS. 2A to 2J are schematic drawings showing the steps of manufacturing a guide panel according to a first preferred embodiment of the present invention.
FIGS. 3A to 3H are schematic drawings showing the steps of manufacturing a guide panel according to a second preferred embodiment of the present invention.
FIGS. 4A to 4I are schematic drawings showing the steps of manufacturing a guide panel according to a third preferred embodiment of the present invention.
FIGS. 5A to 5L are schematic drawings showing the steps of manufacturing a guide panel according to a fourth preferred embodiment of the present invention.
FIGS. 6A to 6K are schematic drawings showing the steps of manufacturing a guide panel according to a fifth preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 2A-2J illustrate the steps for manufacturing a guide panel according to a first preferred embodiment of the present invention. This method is practical for making guide panels in batch at a time. The result guide panel has a plurality of micro feed through holes for the insertion of vertical probe pins respectively such that the movement of the inserted vertical probe pins will be limited to the axial direction of the micro feed through holes so as to prohibit the inserted vertical probe pins from sideway displacement. According to this embodiment, the guide panel fabrication method includes the following steps.
(A) As shown in FIG. 2A, a thin substrate 11 made of a non-metal material, such as Si-based, GaN-based, GaAs-based and InP-based semiconductor materials, or any of other semiconductor materials suitable for anisotropic etching, is prepared. Glasses, ceramics or any of other nonconductive materials suitable for anisotropic etching can also be used for making the thin substrate 11. Preferably, the thin substrate 11 is made of Si-based semiconductor material. The substrate 11 has a first side 111 and a second side 112 opposite to the first side 111, as shown in FIG. 2A.
(B) As shown in FIG. 2B, a first etching masking layer 121 and a second etching masking layer 122 are respectively deposited on the first side 111 and second side 112 of the substrate 11 by low pressure chemical vapour deposition (LPCVD).
(C) As shown in FIG. 2C, a shielding layer 13 having openings 131 with a predetermined pattern is formed on the first etching masking layer 121 by lithography technology. The shielding layer is usually known as a photo resist.
(D) As shown in FIG. 2D, a part of the first etching masking layer 121 corresponding in location to the openings 131 of the shielding layer 13 is removed by the reactive ion etching (RIE) so as to form apertures 123 on the first etching masking layer 12 corresponding to the opening 131 of the shielding layer 13.
(E) Remove the shielding layer 13, as shown in FIG. 2E.
(F) As shown in FIG. 2F, a part of the substrate 11 corresponding in location to the apertures 123 is etched from the first side 111 toward the second side 112 until reaching the second etching masking layer 122 by an anisotropic wet etching so as to form micro feed through holes 113 in the substrate 11 corresponding to the apertures 123. The etchant used for the anisotropic wet etching can be the one selected from the group consisting of KOH, ethylenediamine pyrocatechol (EDP), tetramethyl ammonium hydroxide (TMAH) and hydrazine.
(G) Remove the first etching masking layer 121 and the second etching masking layer 122 from the substrate 11 having the micro feed through holes 113, and therefore the desired guide panel 10 is thus obtained, as shown in FIG. 2G.
By means of the aforesaid manufacturing steps, the guide panels that have precision micro feed through holes spaced from one another at a small pitch can be made in batch at a time. Because the amount of the micro feed through holes does not complicate the manufacturing procedure (micro feed through holes are formed in the same step, i.e. Step F), the above-mentioned method provided by the present invention greatly reduces the manufacturing cost of guide panels and is practical for making guide panels having a large area. As indicted above, since the substrate is preferably made of silicon-based material, which is same as the electronic component under test, the guide panels made by the method of the present invention have the advantage of temperature compensative characteristic.
Further, when making relatively greater area guide panels, the following steps may be added so that prepared guide panels can be cut into small guide panels.
(H) As shown in FIG. 2H, the guide panel 10 thus obtained from the step (G) is cut into multiple small guide panels subject to a predetermined size. FIG. 2I is a top view of the small guide panel.
(I) As shown in FIG. 2J, the small guide panel 10 thus obtained from step (H) is bonded to a seat member 14.
Further, an insulative material, such as SiO₂, Al₂O₃, TiO₂, or any suitable dielectric material, may be coated on the guide panel to enhance the insulative characteristic.
Further, a polymeric material, such as polyimide, may be coated on the guide panel to enhance the toughness of the guide panel or the lubricant characteristic of the micro feed through holes.
FIGS. 3A-3H show a guide panel fabrication method according to a second preferred embodiment of the present invention. According to this embodiment, the guide panel fabrication method includes the following steps.
(A) As shown in FIG. 3A, a thin substrate 21 of a non-metal material, for example a Si-based material in this embodiment, is prepared. The thin substrate 21 has a first side 211 and a second side 212 opposite to the first side 211.
(B) As shown in FIG. 3B, a shielding layer 22 is applied on the first side 211 of the substrate 21.
(C) As shown in FIG. 3C, a plurality of apertures 221 with a predetermined pattern are formed on the shielding layer 22 and reached to the first side 211 of the substrate 21 by the lithograph technology.
(D) As shown in FIG. 3D, blind holes (blind vias) 213 of a predetermined depth are formed on the substrate 21 corresponding in location to the apertures 221 by an anisotropic dry etching selected from the group consisting of the inductively coupled plasma(ICP) etching, plasma etching, ion beam etching, deep reactive ion etching (DRIE) and focus ion beam etching.
(E) Grind the second side 212 of the substrate 21 by the back side thinning technique to open the blind holes 213, thereby forming micro feed through holes 214 through the first side 211 and the second side 212, as shown in FIG. 3E.
(F) As shown in FIG. 3F, the shielding layer 22 is removed; therefore, the desired guide panel 20 is thus obtained.
Similar to the aforesaid first embodiment, the guide panel thus obtained can be cut into small guide panels, i.e. the method further includes the following steps.
(G) As shown in FIG. 3G; the guide panel 20 thus obtained from step (F) is cut into small guide panels 20.
(H) The guide panel 20 thus obtained is bonded to a seat member 23, as shown in FIG. 3H.
Further, an insulative material, such as SiO₂, Al₂O₃, TiO₂, or any suitable dielectric material may be coated on the guide panel to enhance the insulative characteristic.
Further, a polymeric material, such as polyimide, may be coated on the guide panel to enhance the toughness of the guide panel or the lubricant characteristic of the micro feed through holes.
FIGS. 4A-4I show a guide panel fabrication method according to a third preferred embodiment of the present invention. According to this embodiment, the guide panel fabrication method includes the following steps.
(A) As shown in FIG. 4A, a thin substrate 31 of non-metal material, for example a Si-based material in this embodiment, is prepared. The thin substrate 31 has a first side 311 and a second side 312 opposite to the first side 311.
(B) As shown in FIG. 4B, a first oxide layer 321 and a second oxide layer 322 are respectively deposited on the first side 311 and the second side 312 of the substrate 31 by the plasma enhanced chemical vapor deposition (PECVD). According to this embodiment, SiO₂is used for depositing the first oxide layer and the second oxide layer.
(C) As shown in FIG. 4C, a shielding layer 33 is applied on the first oxide layer 321. According to this embodiment, the shielding layer 33 is a photo resist.
(D) As shown in FIG. 4D, a plurality of openings 331 with a predetermined pattern are formed on the shielding layer 33 by the lithography technology.
(E) As shown in FIG. 4E, a part of the first oxide layer 321 corresponding in location to the openings 331 is removed by the reactive ion etching so as to form a plurality of apertures 323 on the first oxide layer 321 corresponding to the openings 331.
(F) As shown in FIG. 4F, a part of the substrate 31 corresponding in location to the apertures 323 is etched from the first side 311 toward the second side 312 until reaching the second oxide layer 322 by the inductively coupled plasma etching so as to form micro feed through holes 313 on the substrate 31.
(G) As shown in FIG. 4G the shielding layer 33 of FIG. 4F is removed.
(H) As shown in FIG. 4H, the first oxide layer 321 and the second oxide layer 322 are removed, thereby obtaining the desired guide panel 30.
If necessary, a further step (I) of cutting the guide panel 30 into small guide panels may be employed, as shown in FIG. 4I.
Further, an insulative material, such as SiO₂, Al₂O₃, TiO₂, or any suitable dielectric material may be coated on the guide panel to enhance the insulative characteristic.
Furthermore, a polymeric material, such as polyimide, may be coated on the guide panel to enhance the toughness of the guide panel or the lubricant characteristic of the micro feed through holes.
FIGS. 5A-5L show a guide panel fabrication method according to a fourth preferred embodiment of the present invention. According to this embodiment, the guide panel fabrication method includes the following steps.
(A) As shown in FIG. 5A, a thin substrate 41 of non-metal material, for example a Si-based material in this embodiment, is prepared. The thin substrate 41 has a first side 411 and a second side 412 opposite to the first side 411.
(B) As shown in FIG. 5B, a first oxide layer 421 and a second oxide layer 422 are deposited on the first side 411 and the second side 412 of the substrate 41 respectively. According to this embodiment, SiO₂is used for depositing the first oxide layer and the second oxide layer.
(C) As shown in FIG. 5C, a first shielding layer 43 made of photo resist is formed on the first oxide layer 421.
(D) As shown in FIG. 5D, a plurality of openings 431 with a predetermined pattern are formed on the first shielding layer 43 and reached to the first oxide layer 421 by the lithography technology.
(E) As shown in FIG. 5E, a part of the first oxide layer 421 corresponding in location to the openings 431 is removed by etching.
(F) As shown in FIG. 5F, a part of the substrate 41 corresponding in location to the openings 431 is etched by the inductively coupled plasma etching or the anisotropic dry etching, such as plasma etching, ion beam etching, deep reactive ion etching (DRIE) and focus ion beam etching, so as to form a plurality of blind holes 46 on the substrate 41, which have a depth and a diameter smaller than the depth and the diameter of the desired micro feed through holes to be made.
(G) As shown in FIG. 5G, a nitride layer 44 is deposited on the top side of the first shielding layer 43 and the bottom side and peripheral wall of each of the openings 431 by the low pressure chemical vapor deposition.
(H) As shown in FIG. 5H, a second shielding layer 45 is applied on the top side of the first shielding layer 43 and then a plurality of through holes 451 on the first shielding layer 43 corresponding in location to the opening 431 are formed by the lithograph technology.
(I) As shown in FIG. 5I, a part of the nitride layer 44 located at the bottom of the openings 431 is removed by means of the reactive ion etching to let a part of the substrate 41 corresponding in location to the openings 431 be accessible from outside.
(J) Use the inductively coupled plasma etching technique to deepen the depth of the blind holes 46 on the substrate 41 until reaching the second oxide layer 422, as shown in FIG. 5J.
(K) As shown in FIG. 5K, the first shielding layer 43 and the second shielding layer 45 are removed.
(L) As shown in FIG. 5L, the first oxide layer 421, the second oxide layer 422 and the nitride layer 44 are removed, thereby obtaining the desired guide panel 40 having micro feed through holes 47.
Further, an insulative material, such as SiO₂, Al₂O₃, TiO₂, or any suitable dielectric material may be coated on the guide panel to enhance the insulative characteristic.
Furthermore, a polymeric material, for example polyimide, may be coated on the guide panel to enhance the toughness of the guide panel or the lubricant characteristic of the micro feed through holes.
FIGS. 6A-6K illustrate a guide panel fabrication method according to a fifth preferred embodiment of the present invention. According to this embodiment, the guide panel fabrication method includes the following steps.
(A) Prepare a thin substrate 51 made of a non-metal material, for example a Si-based material in this embodiment, as shown in FIG. 6A. The thin substrate 51 has a first side 511 and a second side 512 opposite to the first side 511.
(B) Apply a first oxide layer 521 and a second oxide layer 522 on the first side 511 and the second side 512 of the substrate 51 respectively, and then deposit a first nitride layer 531 and a second nitride layer 532 on the first oxide layer 521 and the second oxide layer 522 respectively by the low pressure chemical vapor deposition, as shown in FIG. 6B.
(C) Apply a first shielding layer 53 on the second oxide layer 532, and then form an opening 541 with a predetermined area on the first shielding layer 54 by the lithograph technology, and then remove a part of the second nitride layer 532 corresponding to the opening 541 and a part of the second oxide layer 522 corresponding to the opening 541 by the reactive ion etching technique so as to let a part of the substrate 51 corresponding to the opening 541 be accessible from outside, as shown in FIG. 6C.
(D) Use KOH or any of a variety of other etchant for anisotropic wet etching to etch the part of the substrate 51 corresponding to the opening 541 subject to a predetermined depth and diameter so as to form a recessed portion 513 on the second side 512 of the substrate 51, and then remove the first shielding layer 54 and the first and second nitride layers 531 and 532, as shown in FIG. 6D.
(E) As shown in FIG. 6E, a part of the first oxide layer 521 is etched by the reactive ion etching so as to make a plurality of first apertures 523 of a predetermined pattern and two second apertures 524 on the first oxide layer 521 such that the part of the first side 511 of the substrate 51 corresponding to the first and second apertures 523 and 524 is accessible from outside. The second apertures 524 have a relatively greater diameter than that of the first apertures 523. In addition, the second apertures 524 are located at two opposite lateral sides of the first oxide layer 521.
(F) As shown in FIG. 6F, a second shielding layer 55 is applied on the first oxide layer 521 and then a plurality of through holes 551 are formed on the second shielding layer 55 in communication with the first and second apertures 523 and 524, and then a third shielding layer 56 of a predetermined thickness is deposited on the peripheral wall of each second aperture 524 without blocking the passage between the first side 512 of the substrate 51 and the second apertures 524.
(G) As shown in FIG. 6G, use the inductively coupled plasma etching or the anisotropic dry etching, such as plasma etching, ion beam etching, deep reactive ion etching and focus ion beam etching, to make a plurality blind holes 57 of predetermined depth and diameter on the substrate 51 corresponding to the first and second apertures 523 and 524.
(H) As shown in FIG. 6H, the second shielding layer 55 and the third shielding layer 56 are removed.
(I) Use the inductively coupled plasma etching or the anisotropic dry etching to deepen the depth of the blind holes 57, thereby forming the designed micro feed through holes 58 on the substrate 51 corresponding to the first and second apertures 523 and 524.
(J) As shown in FIG. 6J, the first oxide layer 521 and the second oxide layer 522 are removed, thereby obtaining the desired guide panel 50. As shown in FIG. 6J, the guide panel 50 has a bottom portion acting as the seat member 14 of FIG. 2J. In other words, by means of this method of the fifth embodiment the substrate 11 and the seat member 14 of FIG. 2J can be integrally formed.
FIG. 6K is a top view of FIG. 6J. As shown in FIG. 6K, the two relatively greater through holes at two opposite lateral sides of the guide panel 50 are providing for mounting on an external object.
According to the aforesaid five embodiments, the present invention provides a guide panel fabrication method, which uses the anisotropic etching technique to make micro feed through holes on a substrate so that the guide panels for vertical probe card can be made in batch at a time to save the manufacturing time and to reduce the manufacturing cost. Further, the method of the present invention greatly improves the precision of the micro feed through holes, greatly reduces the pitch between each two adjacent micro feed through holes, and is suitable in making guide panels having relatively large area for vertical probe card. Furthermore, the invention is also practical for making temperature compensated guide panels for vertical probe card.

Claims

1. A method for making a guide panel for a vertical probe card in batch, wherein the guide panel has a plurality of micro feed through holes for insertion of probe pins of the vertical probe card, said method comprising the steps of:

(a) preparing a non-metal substrate;

(b) forming a shielding layer having a plurality of openings with a predetermined pattern on said non-metal substrate; and

(c) forming a plurality of micro feed through holes on said non-metal substrate corresponding to said openings using by an anisotropic etching so as to obtain a guide panel having a plurality of micro feed through holes.

2. The method as claimed in claim 1, wherein said non-metal substrate is made of a material selected from the group consisting of Si-based material, GaN-based material, GaAs-based material and InP-based material.

3. The method as claimed in claim 1, wherein said non-metal substrate is made of a semiconductor material that accepts the anisotropic etching.

4. The method as claimed in claim 1, wherein said non-metal substrate is made of glass or ceramic.

5. The method as claimed in claim 1, wherein said non-metal substrate is made of a nonconductor material that accepts the anisotropic etching.

6. The method as claimed in claim 1, wherein said shielding layer is formed of a photo resist.

7. The method as claimed in claim 1, wherein the openings of said shielding layer are formed by the lithography technology.

8. The method as claimed in claim 1, further comprising the step (d) of coating an insulative material on the guide panel obtained from the step (c).

9. The method as claimed in claim 8, wherein the insulative material is selected from the group consisting of SiO₂, Al₂O₃, and TiO₂.

10. The method as claimed in claim 1, further comprising the step (d) of coating a polymeric material on the guide panel obtained from the step (c).

11. The method as claimed in claim 10, wherein said polymeric material is polyimide.

12. The method as claimed in claim 1, further comprising the step of cutting the guide panel obtained from the step (c) into a plurality of small guide panels.

13. The method as claimed in claim 1, wherein the step (b) includes the sub-steps of:

i) depositing an etching masking layer on said non-metal substrate;

ii) forming a shielding layer having a plurality of openings with a predetermined pattern on said etching masking layer;

iii) etching a part of said etching masking layer corresponding in location to the openings of said shielding layer by a reactive ion etching to form a plurality of apertures on said etching masking layer; and

iv) removing said shielding layer;

wherein the step (c) includes the sub-steps of:

i) etching a part of said non-metal substrate corresponding in location to the apertures to form a plurality of micro feed through holes by an anisotropic wet etching; and

ii) removing said etching masking layer so as to obtain the guide panel.

14. The method as claimed in claim 13, wherein said non-metal substrate has a first side and a second side opposite to said first side, said first side being deposited with a first etching masking layer thereon, said second side being deposited with a second etching masking layer thereon; wherein said shielding layer is formed on said first etching masking layer and the apertures are formed on said first etching masking layer.

15. The method as claimed in claim 13, wherein said anisotropic wet etching uses an etchant selected from the group consisting of KOH, ethylenediamine pyrocatechol, tetramethyl ammonium hydroxide and hydrazine.

16. The method as claimed in claim 13, wherein said etching masking layer is formed of Si₃N₄by means of the low pressure chemical vapor deposition.

17. The method as claimed in claim 1, wherein the anisotropic etching employed in the step (c) is an anisotropic dry etching.

18. The method as claimed in claim 17, wherein the step (c) includes the sub-steps of:

i) forming a plurality of blind holes having a predetermined depth corresponding to the openings of said shielding layer on said substrate by the anisotropic dry etching; and

ii) grinding said substrate to open said blind holes, thereby obtaining the guide panel having a plurality of micro feed through holes.

19. The method as claimed in claim 17, wherein said anisotropic dry etching is selected from the group consisting of inductively coupled plasma etching, plasma etching, ion beam etching, deep reactive ion etching and focus ion beam etching.

20. The method as claimed in claim 17, wherein said non-metal substrate has a first side on which said shielding layer is form, and a second side opposite to said first side.

21. The method as claimed in claim 17, wherein the step (b) includes the sub-steps of:

i) depositing an oxide layer on said non-metal substrate;

ii) forming a shielding layer having openings with a predetermined pattern on said oxide layer; and

iii) etching a part of said oxide layer corresponding in location to the openings by a reactive ion etching to form a plurality of apertures on said oxide layer corresponding to the openings.

22. The method as claimed in claim 21, wherein said oxide layer is formed of SIO₂.

23. The method as claimed in claim 17, wherein the step (c) includes the sub-steps of:

i) etching said non-metal substrate to form a plurality of blind holes having a predetermined depth and diameter corresponding to the openings of said shielding layer by the anisotropic dry etching;

ii) depositing a nitride layer on said first shielding layer and the peripheries of said openings and blind holes;

iii) forming a second shielding layer having through holes corresponding to the openings of said first shielding layer on said first shielding layer;

iv) removing said nitride layer at a bottom side of each of said blind holes by a reactive ion etching;

v) deepening said blind holes by the anisotropic dry etching; and

vi) removing said first shielding layer and said second shielding layer; and

vii) removing the nitride layer.

24. The method as claimed in claim 23, wherein said non-metal substrate has a first side and a second side opposite to said first side, said first side being deposited with a first oxide layer thereon, said second side being deposited a second oxide layer thereon; wherein said first shielding layer is covered on said first oxide layer.

25. The method as claimed in claim 24, wherein said nitride layer is deposited a low pressure chemical vapor deposition.

26. The method as claimed in claim 1, wherein the steps (b) and (c) include the sub-steps of:

i) forming a first oxide layer and a second oxide layer on a first side and a second side of said non-metal substrate respectively;

ii) forming a first nitride layer and a second nitride layer on said first oxide layer and said second oxide layer respectively;

iii) forming a first shielding layer having an opening on said second nitride layer and then removing a part of said second nitride layer and a part of said second oxide layer corresponding in location to the opening of said first shielding layer by a reactive ion etching;

iv) etching said no-metal substrate by an anisotropic wet etching to form a recessed portion on said non-metal substrate corresponding in location to the opening of said first shielding layer;

v) removing said first shielding layer and said first and second nitride layers;

vi) etching said first oxide layer by a reactive ion etching to form a plurality of first and second apertures with a predetermined pattern on said first oxide layer, wherein the second apertures have a diameter grater than that of the first apertures;

vii) forming a second shielding layer on said first oxide layer, said second shielding layer having through holes in communication with the first and second apertures on said first oxide layer;

viii) etching said non-metal substrate by an anisotropic dry etching to form a plurality of blind holes on said non-metal substrate corresponding in location to said first and second apertures;

ix) removing said second shielding layer;

x) deepening said blind holes of said non-metal substrate by an anisotropic dry etching;

xi) removing said first oxide layer and said second oxide layer so as to obtain a guide panel having a recessed portion.

27. A guide panel for a vertical probe card, comprising:

a non-metal substrate having a plurality of micro feed through holes formed by an anisotropic etching for insertion of probes of a vertical probe card.

28. The guide panel as claimed in claim 27, wherein said non-metal substrate is made of a material selected from the group consisting of Si-based material, GaN-based material, GaAs-based material and InP-based material.

29. The guide panel as claimed in claim 27, wherein said non-metal substrate is made of a semiconductor material that accepts the anisotropic etching.

30. The guide panel as claimed in claim 27, wherein said non-metal substrate is made of glass or ceramic.

31. The guide panel as claimed in claim 27, wherein said non-metal substrate is made of a nonconductor material that accepts the anisotropic etching.

32. The guide panel as claimed in claim 27, wherein said anisotropic etching is an anisotropic wet etching.

33. The guide panel as claimed in claim 32, wherein said anisotropic wet etching uses an etchant selected from the group consisting of KOH, ethylenediamine pyrocatechol, tetramethyl ammonium hydroxide and hydrazine.

34. The guide panel as claimed in claim 27, wherein said anisotropic etching is an anisotropic dry etching.

35. The guide panel as claimed in claim 34, wherein said anisotropic dry etching is selected from the group consisting of inductively coupled plasma etching, plasma etching, ion beam etching, deep reactive ion etching and focus ion beam etching.

36. The guide panel as claimed in claim 27, wherein said non-metal substrate is coated with a layer of insulative material.

37. The guide panel as claimed in claim 36, wherein the insulative material is selected from the group consisting of SiO₂, Al₂O₃, and TiO₂.

38. The guide panel as claimed in claim 27, wherein said non-metal substrate is coated with a layer of polymeric material.

39. The guide panel as claimed in claim 38, wherein said polymeric material is polyimide.