BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 through FIG. 3 are schematic diagrams illustrating a conventional micro sample heating apparatus.
FIG. 4 through FIG. 7 are schematic diagrams illustrating a method of fabricating micro sample heating apparatuses according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION
Please refer to FIG. 4 through FIG. 7. FIG. 4 through FIG. 7 are schematic diagrams illustrating a method of fabricating micro sample heating apparatuses according to a preferred embodiment of the present invention. As shown in FIG. 4, a substrate 50 is provided, and an insulating layer 52 is optionally formed on the first surface of the substrate 50. In this embodiment, the substrate 50 is a silicon substrate, but not limited to. The insulating layer 52 can be silicon oxide, silicon nitride, silicon oxynitride, or any suitable single-layer or multi-layer dielectric materials. Subsequently, a plurality of micro heating devices are formed on the insulating layer 52. In this embodiment, the step of forming the micro heating devices includes forming a metal layer 54 and a metal wiring layer 56 on the insulating layer 52. The metal layer 54, which serves as a heating layer, can be a platinum (Pt) layer formed by lift-off techniques, and the metal wiring layer 56 can be formed in the same manner. The metal layer 54 and the metal wiring layer 56 constitute the micro heating devices. It is appreciated that the materials of the metal layer 54 and the metal wiring layer 56 are not limited, and the metal layer 54 and the metal wiring layer 56 can be formed by other methods such as etching.
As shown in FIG. 5, the substrate 50 is turned over, and a plurality of cavities 58 corresponding to the micro heating devices are formed in the second surface of the substrate 50. Each cavity 58 has a vertical sidewall. In this embodiment, the cavities 58 are formed by a deep etching process e.g. an anisotropic dry etching process so as to form the vertical sidewall. It is also appreciated that the substrate 50 can be either etched through or not when forming the cavities 58. In this embodiment, the substrate 50 is etched through, and the insulating layer 52 is an etching stop layer. Therefore, the function of the insulating layer 52 positioned in the bottom of the cavities 58 is equivalent to a slide. The thickness of the insulating layer 52 can be calculated in advance to meet different heating requirements, In addition, the substrate 50 can also be etched without being penetrated. In such a case, the substrate 50 and the insulating layer 52 positioned in the bottom of the cavities 58 both serve as a slide. If the substrate 50 is not etched through, the insulating layer 52 can be omitted.
As shown in FIG. 6, an isolation structure 60 having a plurality of openings 62 is provided. The openings 62 are then aligned to the cavities 58 and the isolation structure 60 is bonded to the second surface of the substrate 50. Each cavity 58 and each opening 62 corresponding to the cavity 58 form a sample room. In this embodiment, the material of the isolation structure 60 is glass, and therefore the isolation structure 60 and the substrate 50 can be adhered together by anodic bonding techniques. However, if a different material is selected, other bonding techniques can be used.
As shown in FIG. 7, a segment process is subsequently performed to divide the substrate 50 and the isolation structure 60 to form the micro sample heating apparatus 70.
In summary, the micro sample heating apparatus and method thereof of the present invention has the following advantages:
1) The method of the present invention is wafer level.
2) The method of the present invention is an integrated method that can improve heating efficiency and the micro sample heating apparatus does not have to be packaged individually.
3) The method of the present invention replaces the slide with a thin film (the substrate and the insulating layer), and therefore reduces heating time.
4) The method of the present invention does not need to assemble the heating unit and the sample room unit.
5) The method of the present invention can reduce the size of the micro sample heating apparatus.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.