The present invention relates to a semiconductor device, and more specifically to a fluid injection device.
Currently, the fluid injection technique is widely used in various products, such as ink jet printheads, fuel oil injection devices, or drug injection mechanism.
A related art fluid injection device is disclosed for example, in U.S. Pat. No. 6,102,530 and illustrated in
A fabrication process for the above chamber 14 is disclosed in the following. Referring to
a shows an original chamber pattern design on a mask and
In order to solve problems related to the conventional technology, the invention provides a fluid injection device having chambers with the same length to eliminate cross-talk while chambers are refilled with fluid.
The invention provides a fluid injection device comprising a substrate, a structural layer formed on the substrate, a manifold installed in the substrate to supply fluid, a plurality of chambers with the same length formed between the substrate and the structural layer to hold injected fluid, a plurality of channels formed between the chambers and the manifold, and a plurality of nozzles through the structural layer and connected with the chambers to inject fluid, wherein the manifold is connected to the chambers by the channels.
Based on the above device structure, when the chambers are refilled with fluid, cross-talk between adjacent chambers can be avoided due to the narrow channels between the chambers and the manifold.
The invention also provides a fluid injection device comprising a substrate, a structural layer formed on the substrate, a manifold installed in the substrate to supply fluid, a plurality of chambers formed between the substrate and the structural layer and connected with the manifold to hold injected fluid, a neck structure installed between the manifold and each chamber, and a plurality of nozzles through the structural layer, connecting the chambers to inject fluid.
The invention further provides a fluid injection device comprising, a substrate, a structural layer formed on the substrate, a manifold installed in the substrate to supply fluid, a plurality of chambers formed between the substrate and the structural layer and connected with the manifold to hold injected fluid, a neck structure installed between the manifold and each chamber, wherein the neck structures have different widths which increase as distances from the chambers to the manifold increase, and a plurality of nozzles through the structural layer, connecting the chambers to inject fluid.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
a˜2c are cross sections illustrating fabrication process of a fluid injection device as disclosed in U.S. Pat. No. 6,102,530.
a shows a related mask pattern.
b illustrates anisotropic etching performance.
a˜4b are cross sections of the method of fabricating a fluid injection device of the invention.
c˜4d, 5a˜5b, 6a˜6b, and 7a˜7b show various mask patterns and etching results of the invention.
Referring to
The above device structure is illustrated in
The structural layer 440 covers the substrate 400, the channels 430, and the chambers 420. The resist layer 450 is installed on the structural layer 440 and on both sides of the nozzles 495. The resist layer 450 represents a plurality of fluid actuators, such as heaters, thereby driving fluid out of the nozzles 455. The isolation layer 460 covers the substrate 400, the structural layer 440, and the resist layer 450, exposing a portion of the resist layer 450 to form heater contacts. The conductive layer 470 covers the isolation layer 460 and fills heater contacts to form signal transmission lines.
The protective layer 480 covers the isolation layer 460 and the conductive layer 470, exposing a portion of the conductive layer 470 to form a plurality of signal transmission line contacts 490, thereby facilitating subsequent packaging process. A plurality of nozzles 495 are formed through the protective layer 480, the conductive layer 470, the resist layer 450, and the structural layer 440, and connected to the chambers 420.
Referring to
The sacrificial layer 405 comprises BPSG, PSG, or silicon oxide, preferably PSG. The thickness of the sacrificial layer 405 is about 1˜2 μm.
Next, a patterned structural layer 440 is formed on the substrate 400 to cover the patterned sacrificial layer 405. The structural layer 440 may be silicon oxide nitride formed by CVD. The thickness of the structural layer 440 is about 1.5˜2 μm. Additionally, the structural layer 440 is a low-stress material, and the stress thereof is about 100˜200 MPa.
Subsequently, a patterned resist layer 450 is formed on the structural layer 440, as fluid actuators, such as heaters, thereby driving fluid out of subsequently formed nozzles. The resist layer 450 comprises HfB2, TaAl, TaN, or TiN, and is preferably TaAl.
A patterned isolation layer 460 is then formed to cover the substrate 400, the structural layer 440, and the resist layer 450, forming heater contacts. Subsequently, a patterned conductive layer 470 is formed on the isolation layer 460, and filled heater contacts to form signal transmission lines. Finally, a protective layer 480 is formed on the isolation layer 460 and the conductive layer 470, exposing the conductive layer 470, thereby forming signal transmission line contacts 490 to facilitate a subsequent packaging process.
Subsequently, referring to
The narrow opening width of the manifold 410 is about 160˜200 μm, and the wide opening width thereof is about 100˜1200 μm. The included angle between the side wall of the manifold 410 and a horizontal factor is about 54.74°. Therefore, after etching, a manifold 410 with a back opening larger than a front opening is formed. Additionally, the manifold 410 connects to a fluid storage tank.
Next, the sacrificial layer 405 is removed by HF, and the substrate 400 is subsequently etched with a basic etching solution, such as KOH or NaOH, to enlarge the vacant volume thereof, forming the chambers 420 and the channels 430, wherein the channels 430 are formed between the chambers 420 and the manifold 410, and lengths (Lc) of the chambers are equal, as shown in
Finally, referring to
The invention provides a specific connection design such as a manifold-channel-chamber on a photomask to compensate for more rapidly etched portion of a substrate to form chambers with the same length to solve the cross-talk problem when chambers are refilled with fluid.
Referring to
The fabrication methods for the injection devices illustrated in
After deposition steps for each semiconductor layer are finished, a series of etching steps are performed to finally form a fluid injection device. The chambers 520 and the neck structures 525 are formed by etching, wherein the neck structures 525 are formed between the chambers 520 and the manifold 510 to form the chambers 520 with the same length (Lc), and the connections of the neck structures 525 and the manifold 510 have the same width, as shown in
The invention provides a specific connection design such as a manifold-neck structure-chamber on a photomask to form chambers with the same length and solve cross-talk problems by forming connections with the same width between the neck structures and the manifold. Additionally, the invention also prevents the formation of etching peaks due to increasing the isolation area 30 as shown in
Referring to
The fabrication methods for the injection devices illustrated in
After deposition steps for each semiconductor layer are finished, a series of etching steps are performed to finally form a fluid injection device. The chambers 620 and the neck structures 625 are formed by etching, wherein the neck structures 625 are formed between the chambers 620 and the manifold 610 to form the chambers 620 with the same length (Lc), and the lengths thereof are also equal, as shown in
The invention provides a specific connection design such as a manifold-neck structure-chamber on a photomask to form chambers with the same length and solve the cross-talk problem and control the flow resistance by forming the neck structures with the same length.
Referring to
The fabrication methods for the injection devices illustrated in
After deposition steps for each semiconductor layer are finished, a series of etching steps are performed to finally form a fluid injection device. The chambers 720 and the neck structures 725 are formed by etching, wherein the neck structures 725 are formed between the chambers 720 and the manifold 710 to form the chambers 720 with the same length (Lc), the lengths thereof are also equal, and the widths of the neck structures 725 are increased as distances from the chambers 720 to the manifold 710 increase, such as Wn3>Wn2>Wn1, as shown in
The invention provides a specific connection design such as a manifold-neck structure-chamber on a photomask to form chambers with the same length and effectively control the flow resistance by forming the neck structures with the altered widths, significantly improving the injection quality.
While the invention has been described by way of example and in terms of preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art) Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
Number | Date | Country | Kind |
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93118757 | Jun 2004 | TW | national |