1280228 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種奈米材料的製作方法，特別是有關於 一種奈米碳纖的製作方法。 【先前技術】 近年來，奈米級的碳管（tube)、碳纖（fiber)、碳線(wire)或碳 棒(rod)等材料已被廣泛應用在各種奈米元件中，例如奈米碳管 (CNT)可應用在掃描式棟針顯微鏡（scanning probe microscope) 的尖端、平面顯示器的場發射元件、單分子電晶體及量子導線 等。 目前，已有許多製作奈米碳管或碳纖的方法，包括例如電 孤放電（arc discharge)、雷射剝餘（iaser ablation)、熱解（pyrolysis) 以及催化分解（catalytic decomposition)等，然而，這些技術均存 在著不少製程限制’如電弧放電或雷射剝蝕並不適合應用在大 規模的量產，而如催化分解則需歷經極高溫的製程步驟等。 在製程限制未克服前，現階段仍以催化分解為較常使用的 方法，此方法係利用鐵、鎳等催化劑，以乙炔當作反應物，在 高溫條件下製造奈米碳管或碳纖，雖後來有如Merkulov等人以 PECVD作為反應器，藉由電漿的辅助試圖降低製程温度，即便 如此’其製程溫度依然高達攝氏700度，或是如Liu等人以 anthracene作為反應物，與氧化鈣反應製作碳纖，亦是需在攝氏 350度的高溫環境下進行，且無論使用爐管或PECvD系統，其 製程反應器的大小都相當有限，無法進行大面積製作。 【發明内容】 0522-A20485TWF(N2)；david 6 1280228 頂部直徑（奈米） 直徑（奈米） 長度（奈米） 110.1 152.5 2576 62.8 82.8 2863 120.3 167.0 3392 70.2 83.3 2675 64.8 67.1 701 76.6 91.0 2078 140.4 283.8 2200 64.8 67.2 2234 97.9 126.8 3371 53.2 66.3 485 表2 由表2可看出，本實施例奈米碳纖的直徑大體介於50〜300 奈米，其平均直徑大體為66奈米，另頂部直徑大體介於30〜200 奈米，且其尖細的頂部結構相當適合應用在場發射（field emission)的元件。 接下來，利用熱脫附系統·大氣常壓游離質譜儀（thermal desorption system-atmospheric pressure ionization mass spectrometer，TDS-APIMS)測試奈米碳纖的熱穩定性，測試步驟 係依每分鐘增加攝氏10度的溫度梯度從25度加熱樣品至800 度，測試結果請參閱第4a及4b圖。 第4a圖係為本實施例多環芳香烴奈米碳纖（PAH-CNF)與 傳統奈米碳管（CNT)兩者的二氧化碳（質荷比為44)熱脫附曲線 比較圖，圖中的曲線a係指本實施例多環芳香烴奈米碳纖 0522-A20485TWF(N2) ；david 10 12802281280228 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a method for producing a nanomaterial, and more particularly to a method for producing a nanocarbon fiber. [Prior Art] In recent years, nanoscale carbon tubes, carbon fibers, wires, or rods have been widely used in various nano components, such as nanocarbon. The tube (CNT) can be applied to the tip of a scanning probe microscope, a field emission element of a flat panel display, a single molecule transistor, a quantum wire, or the like. At present, there are many methods for producing carbon nanotubes or carbon fibers, including, for example, arc discharge, iaser ablation, pyrolysis, and catalytic decomposition. There are many process limitations in these technologies. For example, arc discharge or laser ablation is not suitable for large-scale mass production, and catalytic decomposition requires extremely high temperature process steps. Before the process limitation is overcome, the catalytic decomposition is still a commonly used method at this stage. This method uses iron, nickel and other catalysts to use acetylene as a reactant to produce carbon nanotubes or carbon fibers under high temperature conditions. Later, Merkulov et al. used PECVD as a reactor to try to reduce the process temperature by the aid of plasma. Even if the process temperature is still as high as 700 degrees Celsius, or as an reactant of Liu et al., anthracene as a reactant, react with calcium oxide. The carbon fiber is also produced in a high temperature environment of 350 degrees Celsius, and the size of the process reactor is quite limited regardless of the furnace tube or PECvD system. SUMMARY OF THE INVENTION 0522-A20485TWF(N2);david 6 1280228 Top diameter (nano) Diameter (nano) Length (nano) 110.1 152.5 2576 62.8 82.8 2863 120.3 167.0 3392 70.2 83.3 2675 64.8 67.1 701 76.6 91.0 2078 140.4 283.8 2200 64.8 67.2 2234 97.9 126.8 3371 53.2 66.3 485 Table 2 It can be seen from Table 2 that the diameter of the nano carbon fiber in this embodiment is generally between 50 and 300 nm, and the average diameter is generally 66 nm. It is 30 to 200 nm, and its tapered top structure is quite suitable for components used in field emission. Next, the thermal stability of the nanofibers was tested using a thermal desorption system-atmospheric pressure ionization mass spectrometer (TDS-APIMS). The test procedure was increased by 10 degrees Celsius per minute. The temperature gradient is heated from 25 degrees to 800 degrees. Refer to Figures 4a and 4b for test results. Figure 4a is a comparison diagram of the thermal desorption curves of carbon dioxide (mass-to-charge ratio of 44) of both the polycyclic aromatic hydrocarbon nanofiber (PAH-CNF) and the conventional carbon nanotube (CNT) of the present embodiment, in the figure Curve a refers to the polycyclic aromatic hydrocarbon nano carbon fiber 0522-A20485TWF (N2) of this embodiment; david 10 1280228
(^PAH-CNF)的二氧化碳熱脫附曲線，而 f (CNT)的_氧化碳熱脫附曲線，圖中 :不該兩種產品於加熱過程中苯物種（荷質比為 由苯含量的多募（相對離子強度），再次證明本 實施例含多環芳香煙奈米碳纖的熱穩定性（曲線e)確實較傳统 奈米碳管（曲線d)為佳。 一由於本發明多環芳香烴奈米碳纖（PAH-CNF)可應用於場發 射凡件的製作，遂接著對奈米碳纖進行有關場發射效應的測 試，該項肖試係配合置於奈米碳纖上方且與其輯1〇〇微米直 裎2.2毫米的圓柱型電極來進行，所有測試步驟均在壓力為工〇_ό 托的真空腔室内完成，測試結果請參閱第5圖，圖中可看出， 當電場增加至一定數值後（例如6〜8伏特/微米），電流密度（毫安 培/平方厘米）便開始增加，雖傳統奈米碳管所測得的電流密度 (曲線a)較本發明多環芳香烴奈米碳纖（曲線b)為高，但本發明 的奈米奴纖仍可測得大體1〜2毫安培的場發射電流，而此已足 以作為場發射元件之用。 此外，本發明多環芳香烴奈米碳纖（PAH-CNF)亦可應用於 生化裝置的製作例如DNA或其他生物分子的過濾篩。 總結來說，本發明可利用溫度大約45度及不需催化劑參 與的低溫蒸鍍法進行多環芳香烴奈米碳纖（PAH-CNF)的製作， 且藉由分子間的；Γ- π作用力及基板本身的低自由能，使奈米碳 纖幾乎會以垂直角度成長於基板上，而此基板可為任何材質並 〇522~A20485TWF(N2)；david 11 1280228 不受限，另多環芳香烴奈米碳纖Γ 厌纖（PAH-CNF)的熱穩定性亦較傳 管為佳且具備場發射的特性，此外，相較於習知爐管 或電水輔助氣相沉積系統的反應器，本發明蒸鑛所使用的反應 :尺：明顯較大’遂可同時進行多片鍍膜，具有高產率及低成 本的商業價值。 雖然本發明已以較佳實施例揭露如上，然其並非用以限定 本發明，任何熟習此技藝者，在不脫離本發明之精神和範圍 内，當可作更動與潤飾，因此本發明之保護範圍當視後附之 請專利範圍所界定者為準。 0522-A20485TWF(N2)；david 12 1280228 【圖式簡單說明】 第1圖係為本發明製作奈米碳纖的裝置。 第2圖係本發明奈米碳纖的掃描式電子顯微鏡影像（1)。 第3圖係為本發明奈米碳纖的掃描式電子顯微鏡影像（2)。 第4a圖係為本發明奈米碳纖與習知奈米碳管熱穩定性的比 較圖（1)。 第4b圖係為本發明奈米碳纖與習知奈米碳管熱穩定性的比 較圖（2)。 第5圖係為本發明奈米碳纖與習知奈米碳管的場發射電流 曲線。 【主要元件符號說明】 10〜基板； 20〜蒸鍍腔室； 25〜晶圓載具； 30〜多環芳香烴化合物； 40〜坩鍋。 0522-A20485TWF(N2)；david 13(^PAH-CNF) carbon dioxide thermal desorption curve, and f (CNT) _ carbon oxide thermal desorption curve, in the figure: not the two products in the heating process benzene species (charge-to-mass ratio is from benzene content Multi-raising (relative ionic strength), again proved that the thermal stability (curve e) of the polycyclic aromatic tobacco nanofibers of this example is indeed better than the conventional carbon nanotubes (curve d). Hydrocarbon nanofiber (PAH-CNF) can be applied to the fabrication of field emission parts, and then the nano-carbon fiber is tested for the field emission effect. The XI test is placed on top of the carbon fiber and is combined with it. 〇Micron is a 2.2 mm cylindrical electrode. All the test steps are performed in a vacuum chamber with a pressure of 〇 ό ,. For the test results, please refer to Figure 5. It can be seen that when the electric field increases to a certain value. After the value (for example, 6~8 volts/micron), the current density (milliampere/cm2) begins to increase, although the current density measured by conventional carbon nanotubes (curve a) is higher than the polycyclic aromatic hydrocarbon nanoparticle of the present invention. Carbon fiber (curve b) is high, but the nanofiber of the present invention A field emission current of substantially 1 to 2 milliamperes can be measured, which is sufficient for use as a field emission element. Further, the polycyclic aromatic hydrocarbon nanofiber (PAH-CNF) of the present invention can also be applied to the production of biochemical devices, for example. A filter screen of DNA or other biomolecules. In summary, the present invention can produce polycyclic aromatic hydrocarbon nanofibers (PAH-CNF) by a low temperature vapor deposition method at a temperature of about 45 degrees and without the participation of a catalyst. Intermolecular; Γ-π force and the low free energy of the substrate itself, so that the nano carbon fiber will grow on the substrate almost at a vertical angle, and the substrate can be any material and 〇522~A20485TWF(N2);david 11 1280228 Unrestricted, the thermal stability of another polycyclic aromatic hydrocarbon nanofiber anaerobic fiber (PAH-CNF) is better than that of the tube and has the characteristics of field emission. In addition, compared with the conventional furnace tube or electric water assist The reactor of the vapor deposition system, the reaction used in the steaming of the present invention: the ruler: significantly larger, can carry out multiple coatings at the same time, has high commercial value in high yield and low cost. Although the present invention has been the preferred embodiment Reveal the above, but it is not In order to limit the invention, it is intended that the invention may be modified and modified without departing from the spirit and scope of the invention, and the scope of the invention is defined by the scope of the appended claims. -A20485TWF(N2);david 12 1280228 [Simplified Schematic] Fig. 1 is a device for producing nano carbon fiber according to the present invention. Fig. 2 is a scanning electron microscope image (1) of nano carbon fiber of the present invention. The figure is a scanning electron microscope image of the nano carbon fiber of the invention (2). Fig. 4a is a comparison diagram (1) of the thermal stability of the nano carbon fiber and the conventional carbon nanotube of the present invention. Comparison of the thermal stability of the nano carbon fiber of the present invention and the conventional carbon nanotube (2). Fig. 5 is a graph showing the field emission current of the nano carbon fiber and the conventional carbon nanotube of the present invention. [Main component symbol description] 10~ substrate; 20~ evaporation chamber; 25~ wafer carrier; 30~ polycyclic aromatic hydrocarbon compound; 40~ crucible. 0522-A20485TWF(N2);david 13