本實驗使用熱化學氣相沉積法合成奈米碳管，以鈷薄膜作為催化劑，藉由改變成長碳管的溫度流量比例，壓力並探討各項因子對於碳管密度，石墨化程度以及結構的影響，並藉由此過程得到800 ℃壓力為760 torr時為最穩定之成長參數，並使用於製作元件之控制參數。 本實驗利用靜電場模擬Si/Silicon dioxide/Bottom metal/Co/Top metal元件結構的上下電極的厚度，並發現當上電極厚度大於下電極很多時，催化劑附近的電場會向下，並根據這些結果，規劃出不同的疊層結構來做論證。 根據實驗的結果，可以看出無論是改變疊層結構中上下電極的材料或厚度，都會對成長碳管或是製作元件都會造成很大的影響，在本實驗使用的基版當中 200 nm TaN/7 nm Co/150 nm Pd 是目前作為製作橫向奈米碳管元件較好的結構，並以此結構在成長步驟中加入電場效應成長碳管，發現電場對於碳管成長的方向性有些許的影響，也成功的跨接少數根的奈米碳管於通道兩側，但就結果而言，準直性以及電阻值都不甚理想，我們必需努力探討各項原因，以增加碳管的準直性和降低接觸電阻來改良元件之性能。 We synthesis the multi-wall carbon nanotube(NWCNT) using cobalt catalyst by chemical vapor deposition method with H2 carrir gas and carbon source of CH4 and discuss the effect of CNT density and quality in different temperature, gas ratio and pressure in CNT growth process. From those experiment results the proper condition for CNT growth are 760 torr and 800 ℃. In order to discuss the electric field effect during the CNT growth and design the experiment of metal stack we use electrostatic simulation software to simulate the different thickness of top and bottom metal electrode. From simulation result we got the Horizontal or upward electric field vectors around the Co film were attained when the bottom metal electrode thickness is no less than top metal electrode thickness. According to the experiment result, we discover the significant effect when we use different stack structure to grow CNT (unpattened) and making device. From the substrate we used in this experiment, 200 nm TaN/7 nm Co/150 nm Pd is proper metal stack structure for producing lateral CNT devices. The effect of electric field on lateral CNT growth was observed. However, the improvement is required for the lateral alignment of CNTs and reduction of contact resistances between the CNTs and metal electrodes.
