Patent Application
20120132643
This application claims priority from Korean Patent Application No. 10-2010-0119787, filed on Nov. 29, 2010, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a microheater, and more particularly, to a microheater and a structure of a microheater array in which a width of a connection part between microheaters is adjusted so that the microheater array generally has a uniform temperature distribution, and to a manufacturing method thereof.
2. Description of the Related Art
A microheater is a device for locally generating heat at a desired position on a substrate. Microheaters may be used in electronic devices such as carbon nanotube transistors, polycrystalline silicon thin-film transistors, or the like, or solar cells, which utilize high temperature processes.
A microheater has a structure including a supporting unit formed on a substrate, and a bridge unit supported by the supporting unit and separated from the substrate. When power is applied to the microheater from an external source, the microheater radiates heat so that a local temperature rises.
However, heat transfer in microheaters occur according to conduction via supporting units so that a temperature of the supporting units is low whereas a bridge unit between the supporting units has a high temperature since the bridge unit does not transfer heat to an external source, except for a heat transfer according to convection or radiation. Thus, in such a microheater, temperature differences difference based on location may be high. In a case in which such a temperature difference occurs, it may be difficult to maintain a desired temperature range, and a driving voltage may increase.
One or more exemplary embodiments provide a microheater having a small internal temperature difference, whereby the microheater has a uniform temperature distribution.
One or more exemplary embodiments provide a microheater array having a uniform temperature distribution.
According to an aspect of an exemplary embodiment, a microheater includes a substrate; a column formed on the substrate; and a bridge supported by the column, being separate from the substrate and having a width that varies.
A width of a portion of the bridge that contacts the column may be less than a width of another portion of the bridge that does not contact the column.
The column may be formed of silicon oxide, silicon nitride, or insulating metal oxide.
The bridge may be formed of at least one material selected from the group consisting of molybdenum (Mo), tungsten (W), silicon carbide (SiC), platinum (Pt), and indium-tin-oxide (ITO).
The bridge may include at least one spring component.
The at least one spring component may have a donut shape.
A width of a portion of the bridge that contacts the column may be less than a width of another portion of the bridge that does not contact the column.
A plurality of the columns may be formed on the substrate, and a plurality of the bridges may be formed on the columns in parallel to each other or to cross each other.
These and/or other aspects and advantages will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings in which:
Reference will now be made in detail to exemplary embodiments with reference to the accompanying drawings. In the drawings, the thicknesses of layers and regions may be exaggerated for clarity of the description.
Referring to
Referring to
In the microheater according to the present embodiment, in order to minimize heat loss via the column 11, the width D1 of the portion of the bridge 12 that contacts the column 11 is decreased to prevent excessive heat loss. In the portion of the bridge 12 that is between the columns 11, there is no heat loss other than that which occurs due to convection or radiation. In general, heat of an element is proportional to a resistance of the element, and if a width of the bridge 12 is decreased, the resistance and the generated heat increase. Thus, by decreasing the width D1 of the portion of the bridge 12 that contacts the column 11, a uniform temperature may be maintained in the bridge 12 although a small heat transfer occurs via the column 11. A difference ratio (D1/D2) of widths of the bridge 12 may be selected according to application.
The substrate 10 may be formed of a material including silicon, silicon oxide, silicon nitride, or the like, which are used to form substrates of semiconductor devices, and may be formed of a glass material. The column 11 may be formed of a material having a low thermal conductivity so as to prevent a loss of heat generated in the bridge 12, and may be formed of an insulating material such as silicon oxide, silicon nitride, or another metal oxide. The bridge 12 may be formed of molybdenum (Mo), tungsten (W), silicon carbide (SiC), platinum (Pt) or indium-tin-oxide (ITO), and may have a single-layer structure or a multi-layer structure including one or more materials which radiate heat in response to a power applied thereto. When power is applied to the bridge 12, heat in a visible ray region or an infrared region may be radiated.
A method of manufacturing a microheater, according to an exemplary embodiment will now be described.
First, an insulating material such as silicon oxide or silicon nitride having a low thermal conductivity is coated on a substrate, formed of one of silicon, silicon oxide, silicon nitride, and glass so as to form columns on the substrate. Then, a conductive material including Mo, W, SiC, Pt, or ITO is coated on the insulating material. Next, the conductive material is etched so that bridges having a desired shape are formed. After a predetermined patterning operation is performed, the insulating material other than the columns is removed via an isotropic etching process. The aforementioned method may be performed by using a semiconductor manufacturing process.
Referring to
Referring to
In the structures shown in
In the structure of
The bridge may have shapes with changing widths other than those shown in
However, regardless of a shape of the bridge, a microheater according to one or more exemplary embodiments may include any bridge in which widths of the bridge vary.
Referring to
A level of heat radiation and light emission in each region of the microheater may be determined using a charge-coupled device (CCD) image, and in a microheater according to one or more exemplary embodiments, a region of a bridge contacting a column has a relatively small width so that the microheater may have a uniform temperature distribution.
According to one or more exemplary embodiments, the microheater may have a uniform temperature distribution in its columns and bridges.
Also, according to one or more exemplary embodiments, a microheater array may include microheaters having a uniform temperature distribution.
It should be understood that the exemplary embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects with respect to the exemplary embodiments should be considered as available for other similar features or aspects in other exemplary embodiments, so that an example of a microheater in which a width of a bridge is changed, and a width of a portion of the bridge that contacts a column is reduced may belong to the scope of one or more of the exemplary embodiments.
While exemplary embodiments have been particularly shown and described, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2010-0119787 | Nov 2010 | KR | national |
