Microdevice with movable microplatform and process for making thereof
A process for making a microdevice that includes the steps of providing a base member and selectively electroforming a support member for supporting a microplatform with respect to the base member. The process also includes the steps of selectively electroforming the microplatform and forming a flexible hinge member for hingedly connecting the microplatform to the support member and allowing relative movement of the microplatform with respect to the support member. This microdevice, when compared to prior art devices, can have improved mechanical strength, rigidity, low deformation, and high planarity.
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The present invention relates to a microdevice and a process for making thereof, but more particularly, to a microdevice equipped with a movable microplatform and a process for making thereof.
BACKGROUND OF THE INVENTIONThere are several examples of miniature electromechanical devices equipped with movable microplatforms with lateral dimensions from a few micrometers to several thousands of micrometers. The pivoting along one or multiple axis, and vertical or horizontal displacement of these microplatforms is possible due to various types of hinge members including torsional and flexure hinge types. The movement of the microplatforms is induced typically via electrostatic, magnetic or thermal mechanisms.
The functions performed by these microdevices equipped with movable microplatforms include phase and amplitude modulation of visible, UV or IR radiation beams as well as mechanical protection with open and close functions of specialty microsystems. In particular, the microdevices used for radiation beam manipulation are often called micromirror devices and find multiple applications in telecom for laser beam attenuation and switching as well as in projection imagers as the spatial light modulators.
In optical applications in particular, it is extremely important to provide movable microplatforms that are free of mechanical deformations and defects, with a residual radius of curvature of many meters and surface roughness better than λ/10, where λ is the wavelength of radiation used.
There are typically two methods used for manufacturing individual and arrays of microdevices equipped with movable microplatforms. The first most commonly used method makes use of a thin film technology developed for manufacturing integrated circuits (ICs), while the second method typically involves micromachining silicon wafers and epitaxial silicon films by a deep etching technique.
Known in the art is U.S. Pat. No. 6,025,951 by N. R. Swart et al, which discloses a micromirror device equipped with a flexure hinge permitting to tilt as well as to displace vertically a microplatform via the electrostatic interaction. Methods for forming individual or multiple microdevices are also described. These methods make use of the thin film technology developed for manufacturing ICs.
The biggest drawback of the microplatforms produced by the thin film technology is a residual stress in the deposited thin films as well as a mismatch between stresses in films made of different materials. This produces deviations from the platform flatness required and thus adversely affects the microdevice performance. Typically, the residual stress in thin films scales inversely with the film thickness. However, the thin film technology yields a film with a thickness not exceeding a few micrometers and thus the stress reduction is not sufficient. Thin films also have rough surfaces, which contributes to unwanted scattering of radiation illuminating the microplatform.
Also known in the art is U.S. Pat. 4,317,611 by K. E. Petersen, which discloses a torsional-type optical ray deflection apparatus produced out of a pair of etched plates, one of which is single crystal semiconductor material such as silicon, and the other is a suitable insulating material such as glass. A pivoting microplatform equipped with torsional hinges is made by anisotropic etching through a silicon wafer. It is then bonded to a glass plate equipped with suitable metal electrodes for electrostatic activation of the microplatform.
Also known in the art is U.S. Pat. 6,044,705 by A. P. Neukermans et al, which discloses a different approach to manufacturing of pivoting microplatform devices making use of a stress-free semiconductor layer of silicon. The epitaxial silicon layer with a thickness ranging from less than one to tens of micrometers is grown on the etch stop layer deposited on the Si wafer.
Also known in the art, there are U.S. patent application 2001/0044165 A1 by S. B. Lee et al. and U.S. Pat. No. 6,353,492 B2 by R. W. McClelland, which disclose pivoting microplatform devices made entirely from monocrystalline silicon wafers by the deep etching technique.
Application of silicon in the form of polished wafers or epitaxial layers deposited on silicon wafers allows to alleviate some limitations associated with the thin film technology. Silicon in this form is light, strong and stiff, yielding rigid microplatforms with low moment of inertia. It also yields a wide range of microplatform thicknesses from tens to hundreds of micrometers. Silicon wafers can be polished to provide excellent surface quality (i.e. very low roughness) and flatness. They will reflect radiation effectively when covered with appropriate coatings. On the other hand, patterning of silicon wafers may be a limiting factor in terms of minimum feature size or geometrical form especially if the anisotropic wet etching technique is applied. Moreover, the microdevices equipped with movable monocrystalline silicon microplatforms are typically of hybrid construction. They consist of at least two different parts, one comprising the microplatform and the other one performing a function of the supporting base equipped with electrodes and contact pads for actuation of the microplatform. Fully monolithic devices are difficult to implement and are mostly formed by the competing thin film technology.
The following United States patents disclose other devices suffering from the same drawbacks as described above: U.S. Pat. No. 5,083,857 (L. J. Hornbeck); U.S. Pat. No. 5,212,582 (W. E. Nelson); U.S. Pat. No. 5,233,456 (W. E. Nelson); U.S. Pat. No. 5,312,513 (J. M. Florence et al.); and U.S. Pat. No. 5,789,264 (J. H. Chung).
SUMMARY OF THE INVENTIONAn object of the present invention is to provide a process for making a microdevice equipped with a movable microplatform that overcomes the above-identified drawbacks of the prior art devices. In particular, a preferred microdevice according to the present invention can have improved mechanical strength, rigidity, low deformation, and high planarity. The microdevice may also be fully monolithic.
According to the present invention, there is provided a process for making a microdevice, comprising the steps of:
-
- a) providing a base member;
- b) selectively electroforming at least one support member for supporting a microplatform with respect to the base member;
- c) selectively electroforming the microplatform; and
- d) forming at least one flexible hinge member for hingedly connecting the microplatform to said at least one support member and allowing relative movement of the microplatform with respect to said at least one support member.
According to another aspect of the present invention, there is provided a microdevice comprising:
-
- a base member;
- at least one support member mountably connected to the base member, said at least one support member being selectively electroformed according to a selective electroforming process;
- at least one hinge member mountably connected to said at least one support member; and
- a microplatform hingedly connected to said at least one hinge member for allowing relative movement of the microplatform with respect to said at least one support member, the microplatform being selectively electroformed according to a selective electroforming process.
Other objects, advantages and features of the present invention will become more apparent upon reading of the following non-restrictive description of preferred embodiments thereof, given by way of example only with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1B1, 1B2 and 1B3 are top views of microplatforms with hinge members attached thereto according to different preferred embodiments of the present invention.
Referring to
Referring to
-
- a) providing a base member;
- b) selectively electroforming at least one support member 4 for supporting a microplatform 2 with respect to the base member;
- c) selectively electroforming the microplatform 2; and
- d) forming at least one flexible hinge member 3 for hingedly connecting the microplatform 2 to the at least one support member 4 and allowing relative movement of the microplatform 2 with respect to the at least one support member 4.
Referring now to
-
- step b) comprises the step of mountably connecting the at least one support member 4 to the base member;
- step d) is performed after step b) and before step c) and comprises the step of mountably connecting the at least one hinge member 3 to the at least one support member 4; and
- step c) comprises the step of mountably connecting the microplatform 2 to the at least one hinge member 3.
Referring to now
-
- step c) is performed before steps a), b) and d) and comprises the step of selectively electroforming the microplatform 2 on a sacrificial substrate 20;
- step d) is performed before steps a) and b) and comprises the step of mountably connecting the at least one hinge member 3 to the microplatform 2;
- step b) is performed before step a) and comprises the steps of mountably connecting the at least one support member 4 to the at least one hinge member 3 and removing the sacrificial substrate 20; and
- step a) comprises the step of mountably connecting the at least one support member 4 to the base member.
The above first and second preferred processes will be explained in more details herein below. Of course, several modifications may be effected thereto as those skilled in the art will understand.
As explained above, the process according the present invention is based on the selective electroforming technique (i.e. localized electroforming), which makes use of photolithographically patterned photoresist layers as precise masks defining the regions on a given substrate where the materials are electrolytically deposited. Generally, electroforming, as opposed to other film deposition techniques such as thermal evaporation or sputtering, offers several advantages including: a broad range of deposited materials (principally pure metals, metal alloys and organoceramic dielectrics), near room temperature processing using relatively low-cost equipment and facilities, high deposition rate and film thickness range from below 1 μm to several hundred of micrometers, stress free films, and conformal or selective deposition with excellent shape fidelity. The direct or pulse current electroforming allows a precise control of the material properties, including its composition, crystallographic structure, texture and grain size. Moreover, stacking of thin layers with different compositions can be obtained with relative ease. Typical list of electroformed materials include: Au, Cr, Cu, Ni, Zn, Ag, Fe, Ni—Fe, In, PbSn, and organoceramics.
Modern photoresist materials offer selective photopatterning capabilities with submicrometer resolution, and masking layer thicknesses from a fraction of 1 μm to over 100 μm. With respect to forming the microdevices 1 equipped with movable microplatforms 2, the fabrication processes according to the present invention offer a reliable manufacturing of mechanically solid supports for the microplatforms 2, as well as the manufacturing of these platforms with thicknesses up to tens and even hundreds of micrometers which guarantees their mechanical strength, rigidity, low deformation, and high planarity. This provides a unique opportunity for forming microdevices 1 with microplatforms 2 with lateral dimensions of hundreds or even thousands of micrometers and a wide range of tilt angles (up to 90°) and displacements (several micrometers). Moreover, the forming processes make possible the manufacturing of microdevices being integrated parts of semiconductor substrates equipped with integrated electronic circuits or microdevices which can be in a hybrid fashion attached via soldering, gluing etc. to other substrates made of glass, ceramic or semiconductor. This offers an enormous flexibility in designing functional devices optimized for particular applications and operational environment.
Referring now to
Referring to
In a typical selective electroforming operation, the substrate 5 or sacrificial substrate 20 are placed in a holder which allows electrical contact through the seed layers 11 or 21. This holder is then dipped in the electroplating bath so that the substrate faces the anode consisting of the metal to be plated or a platinized grid. A constant or pulsed current is then applied between the anode and stationary or rotating cathode so that the electrochemical reduction and consequently metal deposition can take place. The electroforming time is proportional to the thickness of deposited metal. The wafer is then rinsed and dried prior to subsequent processing steps.
Referring to
There is a possibility that the separation step illustrated in
As mentioned above, the microdevices 1 that are formed according to the process of the present invention can provide mechanically solid support members 4 and microplatforms 2, with thicknesses up to tens and even hundreds of micrometers. These microdevices 1, when compared to the prior art devices, have improved mechanical strength, rigidity, low deformation, and high planarity. This provides a unique opportunity for forming microdevices 1 with microplatforms 2 with lateral dimensions of hundreds or even thousands of micrometers and a wide range of tilt angles (up to 90°) and displacements (several micrometers). Moreover, the proposed forming processes make possible the manufacturing of microdevices 1 being integrated parts of semiconductor substrates equipped with integrated electronic circuits or microdevices which can be in a hybrid fashion attached via soldering, gluing etc. to other substrates made of glass, ceramic or semiconductor. This offers an enormous flexibility in designing functional devices optimized for particular applications and. operational environment.
Although preferred embodiments of the present invention have been described in the context of manufacturing a single microdevice equipped with a movable microplatform, the same embodiments can be applied to manufacturing in a single process of arrays of several microdevices at the same time. Moreover, it is to be understood that the invention described in detail herein and illustrated in the accompanying drawings is not limited to these precise embodiments and that various changes and modifications may be effected therein without departing from the scope or spirit of the present invention.
Claims
1-13. (canceled)
14. A microdevice comprising:
- a base member;
- at least one selectively electroformed support member mountably connected to the base member;
- at least one selectively electroformed hinge member mountably connected to said at least one support member; and
- a selectively electroformed microplatform hingedly connected to said at least one hinge member for allowing relative movement of the microplatform with respect to said at least one support member.
15-20. (canceled)
21. A process for making the microdevice as defined in claim 14, the process comprising the steps of:
- a) providing the base member;
- b) selectively electroforming said at least one support member for supporting a microplatform with respect to the base member, said at least one support member being selectively electroformed in at least one first opening that is produced by photolitographically patterning a first photoresist layer;
- c) selectively electroforming the microplatform, the microplatform being selectively electroformed in a second opening that is produced by photolitographically patterning a second photoresist layer; and
- d) selectively electroforming said at least one flexible hinge member for hingedly connecting the microplatform to said at least one support member and allowing relative movement of the microplatform with respect to said at least one support member, said at least one flexible hinge member being selectively electroformed in at least one third opening that is produced by photolitographically patterning a third photoresist layer.
22. The process for making the microdevice (according to claim 21, wherein:
- step b) comprises the step of mountably connecting said at least one support member to the base member;
- step d) is performed after step b) and before step c) and comprises the step of mountably connecting said at least one hinge member to said at least one support member; and
- step c) comprises the step of mountably connecting the microplatform to said at least one hinge member.
23. The process for making the microdevice according to claim 22, wherein step a) comprises the steps of:
- i) providing a substrate;
- ii) connecting at least one electrode and at least one contact pad onto a side of the substrate;
- iii) covering said side with a protective layer; and
- iv) providing at least one opening in the protective layer for accessing said at least one contact pad, thereby providing the base member.
24. The process for making the microdevice according to claim 23, wherein step b) comprises the steps of:
- v) covering, after step iv), said side with a first seed layer;
- vi) covering, after step v), said side with the first photoresist layer; and
- vii) photolitographically patterning the first photoresist layer to produce said at least one first opening on the first photoresist layer that is aligned with said at least one opening for accessing said at least one contact pad, said at least one support member being selectively electroformed in said at least one first opening of the first photoresist layer.
25. The process for making the microdevice according to claim 24, wherein step d) comprises the steps of:
- viii) covering, after step vii), said side with a second seed layer;
- ix) covering the second seed layer with the third photoresist layer; and
- x) photolitographically patterning the third photoresist layer to produce said at least one third opening on the third photoresist layer that is aligned with said at least one support member, said at least one hinge member being selectively electroformed in said at least one third opening of the third photoresist layer.
26. The process for making the microdevice according to claim 25, wherein step c) comprises the steps of:
- xi) removing, after step x), the third photoresist layer;
- xii) covering, after step xi), said side with the second photoresist layer;
- xiii) photolitographically patterning the second photoresist layer to produce the second opening on the second photoresist layer, the microplatform being selectively electroformed in the second opening of the second photoresist layer;
- xiv) removing, after step xiii), the second photoresist layer;
- xv) selectively removing, after step xiv), a part of the second seed layer that is unprotected by said at least one hinge member;
- xvi) removing, after step xv), the first photoresist layer; and
- xvii) removing, after step xvi), the first seed layer and another part of the second seed layer unprotected by said at least one support member for defining a cavity between the microplatform and the base member.
27. The process for making the microdevice according to claim 26, wherein step c) further comprises the step of polishing an upper surface of the microplatform after step xiii).
28. The process for making the microdevice according to claim 21, wherein:
- step c) is performed before steps b) and d) and comprises the step of selectively electroforming the microplatform on a sacrificial substrate;
- step d) is performed before step b) and comprises the step of mountably connecting said at least one hinge member to the microplatform;
- step b) comprises the steps of mountably connecting said at least one support member to said at least one hinge member, and removing the sacrificial substrate; and
- step a) comprises the step of mountably connecting said at least one support member to the base member, after the step of removing the sacrificial substrate.
29. The process for making the microdevice according to claim 28, wherein step c) comprises the steps of:
- i) covering a side of the sacrificial substrate with a first seed layer;
- ii) covering the first seed layer with the second photoresist layer; and
- iii) photolitographically patterning the second photoresist layer to produce the second opening on the second photoresist layer, the microplatform being selectively electroformed in the second opening of the second photoresist layer.
30. The process for making the microdevice according to claim 29, wherein step d) comprises the steps of:
- iv) covering, after step iii), said side with a second seed layer;
- v) covering, after step iv), said side with the third photoresist layer;
- vi) photolitographically patterning the third photoresist layer to produce said at least one third opening on the third photoresist layer that is aligned with the microplatform; and
- vii) selectively electroforming said at least one hinge member in said at least one third opening of the third photoresist layer.
31. The process for making the microdevice according to claim 30, wherein step b) comprises the steps of:
- viii) removing, after step vii), the third photoresist layer;
- ix) covering, after step viii), said side with the first photoresist layer;
- x) photolitographically patterning the first photoresist layer to produce said at least one first opening on the first photoresist layer, said at least one support member being selectively electroformed in said at least one first opening of the first photoresist layer;
- xi) selectively electroforming, after step x), a soldering material on said at least one support member;
- xii) removing, after step xi), the first photoresist layer;
- xiii) removing, after step xii), a part of the second seed layer unprotected by said at least one support member and hinge member;
- xiv) removing, after step xiii), the second photoresist layer; and
- xv) removing, after step xiv), the first seed layer for separating the sacrificial substrate from the microplatform.
32. The process for making the microdevice according to claim 31, wherein step a) comprises the steps of:
- xvi) providing a substrate;
- xvii) connecting, after step xvi), at least one electrode and at least one contact pad onto a side of the substrate;
- xviii) covering the side of said substrate with a protective layer;
- xix) providing at least one opening in the protective layer for accessing said at least one contact pad, thereby providing the base member; and
- xx) soldering, after step xix), said at least one support member onto the base member, via the soldering material and said at least one contact pad.
33. The process for making the microdevice according to claim 21 wherein:
- step b) is performed before steps c) and d) and comprises the step of selectively electroforming said at least one support member on a sacrificial substrate;
- step d) is performed before step c) and comprises the step of mountably connecting said at least one hinge member to said at least one support member;
- step c) comprises the steps of mountably connecting the microplatform to said at least one hinge member, and removing the sacrificial substrate; and
- step a) comprises the step of mountably connecting said at least one support member of the base member, after the step of removing the sacrificial substrate.
34. The process for making the microdevice according to claim 33, wherein step b) comprises the steps of:
- i) covering a side of the sacrificial substrate with a first seed layer;
- ii) covering the first seed layer with the first photoresist layer; and
- iii) photolitographically patterning the first photoresist layer to produce said at least one first opening on the first photoresist layer, said at least one support member being selectively electroformed in said at least one first opening of the first photoresist layer.
35. The process for making the microdevice according to claim 34, wherein step iii) comprises the step of selectively electroforming a soldering material on said at least one first opening before said at least one support member is selectively electroformed therein.
36. The process for making the microdevice according to claim 34, wherein step d) comprises the steps of:
- iv) covering, after step iii), said side with a second seed layer;
- v) covering, after step iv), said side with the third photoresist layer;
- vi) photolitographically patterning the third photoresist layer to produce said at least one third opening on the third photoresist layer that is aligned with said at least one support member; and
- vii) selectively electroforming said at least one hinge member in said at least one third opening of the third photoresist layer.
37. The process for making the microdevice according to claim 36, wherein step c) comprises the steps of:
- viii) removing, after step vii), the third photoresist layer;
- ix) covering, after step viii), said side with the second photoresist layer;
- x) photolitographically patterning the second photoresist layer to produce the second opening on the second photoresist layer, the microplatform being selectively electroformed in the second opening of the second photoresist layer;
- xi) removing, after step x), the second photoresist layer;
- xii) removing, after step xi), a part of the second seed layer unprotected by said at least one support member and hinge member;
- xiii) removing, after step xii), the first photoresist layer; and
- xiv) removing, after step xiv), the first seed layer for separating the sacrificial substrate from the soldering material.
38. The process for making the microdevice according to claim 37, wherein step a) comprises the steps of:
- xv) providing a substrate;
- xvi) connecting, after step xv), at least one electrode and at least one contact pad onto a side of the substrate;
- xvii) covering the side of said substrate with a protective layer;
- xviii) providing at least one opening in the protective layer for accessing said at least one contact pad, thereby providing the base member; and
- xix) soldering, after step xviii), said at least one support member onto the base member, via the soldering material and said at least one contact pad.
39. The process for making the microdevice according to claim 21, wherein:
- step d) is performed before step c) and comprises the step of selectively electroforming said at least one hinge member on a sacrificial substrate;
- step c) comprises the steps of mountably connecting the microplatform to said at least one hinge member and removing the sacrificial substrate; and
- step b) is performed after step a) and comprises the step of mountably connecting said at least one support member to the base member.
40. The process for making the microdevice according to claim 39, wherein:
- step d) comprises the steps of: i) covering a side of the sacrificial substrate with a first seed layer; ii) covering the first seed layer with the third photoresist layer; and iii) photolitographically patterning the third photoresist layer to produce said at least one third opening on the third photoresist layer, said at least one hinge member being selectively electroformed in said at least one third opening of the third photoresist layer.
41 The process for making the microdevice according to claim 40, wherein step iii) comprises the step of selectively electroforming a soldering material on said at least one third opening before said at least one hinge member is selectively electroformed therein.
42. The process for making the microdevice according to claim 41, wherein step c) comprises the steps of:
- iv) covering, after step iii), said side with a second seed layer;
- v) covering, after step iv), said side with the second photoresist layer;
- vi) photolitographically patterning the second photoresist layer to produce the second opening on the second photoresist layer that is aligned with said at least one hinge member;
- vii) selectively electroforming the microplatform in the second opening of the second photoresist layer;
- viii) removing, after step vii), the second photoresist layer;
- ix) removing, after step viii), a part of the second seed layer unprotected by the microplatform;
- x) removing, after step ix), the third photoresist layer; and
- xi) removing, after step x), the first seed layer for separating the sacrificial substrate from the soldering material.
43. The process for making the microdevice according to claim 42, wherein:
- step a) comprises the steps of: xii) providing a substrate; xiii) connecting, after step xii), at least one electrode and at least one contact pad onto a side of the substrate; xiv) covering the side of said substrate with a protective layer; and xv) providing at least one opening in the protective layer for accessing said at least one contact pad, thereby providing a base member; and
- step b) comprises the steps of: xvi) covering, after step xv), said side with a third seed layer; xvii) covering, after step v), said side with the first photoresist layer; xviii) photolitographically patterning the first photoresist layer to produce said at least one first opening on the first photoresist layer that is aligned with said at least one opening for accessing said at least one contact pad, said at least one support member being selectively electroformed in said at least one first opening of the first photoresist layer; xix) removing, after step xviii), the first photoresist layer; xx) selectively removing, after step xix), a part of the third seed layer unprotected by said at least one support member; and xxi) soldering, after step xx), said at least one hinge member onto said at least one support member, via the soldering material.
44. The process for making the microdevice according to claim 40, wherein step b) comprises the step of selectively electroforming a soldering material on said at least one support member.
45. The process for making the microdevice according to claim 44, wherein step c) comprises the steps of:
- iv) covering, after step iii), said side with a second seed layer;
- v) covering, after step iv), said side with the second photoresist layer;
- vi) photolitographically patterning the second photoresist layer to produce the second opening on the second photoresist layer that is aligned with said at least one hinge member;
- vii) selectively electroforming the microplatform in the second opening of the second photoresist layer;
- viii) removing, after step vii), the second photoresist layer;
- ix) removing, after step viii), a part of the second seed layer unprotected by the microplatform;
- x) removing, after step ix), the third photoresist layer; and
- xi) removing, after step x), the first seed layer for separating the sacrificial substrate from the hinge.
46. The process for making the microdevice according to claim 45, wherein:
- step a) comprises the steps of: xii) providing a substrate; xiii) connecting, after step xii), at least one electrode and at least one contact pad onto a side of the substrate; xiv) covering the side of said substrate with a protective layer; and xv) providing at least one opening in the protective layer for accessing said at least one contact pad, thereby providing the base member; and
- step b) comprises the steps of: xvi) covering, after step xv), said side with a third seed layer; xvii) covering, after step v), said side with the first photoresist layer; xviii) photolitographically patterning the first photoresist layer to produce said at least one first opening on the first photoresist layer that is aligned with said at least one opening for accessing said at least one contact pad, said at least one support member being selectively electroformed in said at least one first opening of the first photoresist layer; xix) removing, after step xviii), the first photoresist layer; xx) selectively removing, after step xix), a part of the third seed layer unprotected by said at least one support member; and xxi) soldering, after step xx), said at least one hinge member onto said at least one support member, via the soldering material.
47. The process for making the microdevice according to claim 21, wherein:
- step d) is performed before step c) and comprises the step of selectively electroforming said at least one hinge member on a sacrificial substrate;
- step c) comprises the steps of mountably connecting the microplatform to said at least one hinge member;
- step b) is performed after step c) and comprises the steps of mountably connecting said at least one support member to said at least one hinge member and microplatform, and removing the sacrificial substrate (20); and
- step a) is performed after step b) and comprises the step of mountably connecting said at least one support member to the base member.
48. The process for making the microdevice according to claim 47, wherein step d) comprises the steps of:
- i) covering a side of the sacrificial substrate with a first seed layer;
- ii) covering the first seed layer with the third photoresist layer; and
- iii) photolitographically patterning the third photoresist layer to produce at least one third opening on the third photoresist layer, said at least one hinge member being selectively electroformed in said at least one third opening of the third photoresist layer.
49. The process for making the microdevice according to claim 48, wherein step c) comprises the steps of:
- iv) removing, after step iii), the third photoresist layer;
- v) covering, after step iv), said at least one hinge member with the second photoresist layer;
- vi) photolitographically patterning the second photoresist layer to produce the second opening on the second photoresist layer that is aligned with said at least one hinge member; and
- vii) selectively electroforming the microplatform in the second opening of the second photoresist layer.
50. The process for making the microdevice according to claim 47, wherein step b) comprises the step of selectively electroforming a soldering material on said at least one support member, before the step of mountably connecting said at least one support member to the base member.
51. The process for making the microdevice according to claim 50, wherein step b) comprises the steps of:
- viii) removing, after step vii), the second photoresist layer;
- ix) covering, after step viii), said microplatform with the first photoresist layer;
- x) photolitographically patterning the first photoresist layer to produce said at least one first opening on the first photoresist layer that is aligned with said microplatform, said at least one support member being selectively electroformed in said at least one first opening of the first photoresist layer;
- xi) removing, after step x), the first photoresist layer;
- xii) removing, after step xi), the first seed layer for separating the sacrificial substrate (20) from said at least one hinge member; and
- xiii) soldering, after step xii), said at least one support member onto said base member via the soldering material.
52. The process for making the microdevice according to claim 51, wherein step a) comprises the steps of:
- xiv) providing a substrate;
- xv) connecting, after step xiv), at least one electrode and at least one contact pad onto a side of the substrate;
- xvi) covering the side of said substrate with a protective layer; and
- xvii) providing at least one opening in the protective layer for accessing said at least one contact pad, thereby providing the base member.
Type: Application
Filed: Jan 31, 2005
Publication Date: Oct 20, 2005
Applicant: Institut National D'Optique (Sainte-Foy)
Inventors: Hubert Jerominek (Sainte-Foy), Patrice Topart (Cap-Rouge)
Application Number: 11/048,298