Studies on selective productions of radicals using electron temperature controlled plasmas

我们已经实现了自由基的选择性生产，通过结合原料气体和各种等离子体源如下：1。研究表明，通过控制电子束激发N_2等离子体的电子束能量和电流，可以控制氮自由基的密度，这是一种很有前途的低气压高密度氮自由基源。此外，我们还开发了一种新型的紧凑型EBEP源，不仅适用于高密度自由基源，而且还适用于类金刚石碳沉积和玻璃基板表面清洁的过程。在类金刚石薄膜的沉积过程中，我们成功地在电浮置衬底上合成了类金刚石薄膜.首次在1.3Pa的低气压下，通过选择性地产生CH_3、H和OH自由基而不是C原子，并通过控制中性自由基和离子自由基的比例，成功地合成了纳米金刚石.我们用超高频（UHF，500 MHz）电源实现了电子温度为0.5eV的硅烷/氢等离子体，并发现可以通过脉冲调制等离子体来控制Si原子与H原子的比例。此外，我们还发现通过控制Si/H原子比和SiH_3/H自由基比可以控制沉积微晶硅薄膜的结晶度和取向.我们发现，在UHF N_2/H_2/NH_3等离子体中，氮原子密度比RF（13.56MHz）N_2/H_2/NH_3等离子体中的氮原子密度有选择地增加，实现了对低介电有机薄膜的精细各向异性刻蚀。

We have achieved selective productions of radicals by combining feed gases and various plasma sources as follows ;1. We have clarified that nitrogen radical density can be controlled through controlling the electron beam energy and current of electron-beam excited N_2 plasma, which is a promising high-density nitrogen radical source under ultra low operating pressures. Moreover, we have developed a novel compact EBEP source and applied to not only high-density radical sources but also to processes of diamond-like carbon deposition and surface cleaning of glass substrates. In the deposition process of diamond-like carbon, we have successfully synthesized the diamond-like carbon films on electrically floating substrates.2. We have successfully synthesized nano-crystalline diamond at the low operating pressure of 1.3Pa for the first time by producing CH_3, H, and OH radicals selectively rather than C atoms and by controlling the ratio of neutral radicals to ionic radicals.3. We have realized silane/hydrogen plasmas with very low electron temperature of 0.5 eV by using ultra-high frequency (UHF, 500MHz) power supply and found that the ratio of Si atom to H atom can be controlled by using pulse modulation of the plasma. Moreover, we have found that the crystallinity and orientation of deposited microcrystallin silicon film can be controlled by controlling Si/H atom ratio and SiH_3/H radical ratio.4. We have found that the nitrogen atom density in UHF N_2/H_2/NH_3 plasma can be selectively enhanced compared to that in RF (13.56MHz) N_2/H_2/NH_3 plasma and realized the very fine anisotropic etching of low dielectric organic films.