标题: 超薄含氮氧化层创新制程技术应用在n型金氧半场效电晶体之特性研究
New Advanced Process of Ultrathin Oxynitride on the Characteristics of nMOSFET
作者: 叶建宏
Chien-Hung Yeh
叶清发
罗正忠
Chin-Fa Yeh
Jen-Chung Lou
电子研究所
关键字: 超薄;含氮氧化层;电晶体;Ultra-thin;Oxynitride;Mosfet
公开日期: 2006
摘要: 摘 要
   随着元件尺寸的微缩,极薄的二氧化矽介电层将伴随着极大的直接穿遂漏电流,而这个直接穿遂漏电流将对元件的功率消耗有严重的影响。在闸极二氧化矽介电层薄到10奈米以下,将会随着严重的漏电流,为了解决这严重的直接穿遂现象,我们将利用高介电系数材料来替换传统的二氧化矽。我们利用的高介电系数材料在相同的等效二氧化矽厚度下,能拥有较大的实际物理厚度以抵挡直接穿遂的漏电流。
   在先前的报告已指出,含氮氧化层拥有许多传统氧化层所没有的优点,例如,有好的抵抗硼扩散的能力、能有效的防御高电场所照成的热载子破坏、有较高的介电强度等优点。对于深次微米的ULSI的制程来说,含氮氧化层是能有效的去改善传统氧化层的缺点而成为主流应用。
   我们提出了新的方法能在多晶矽和介电层的介面上形成高氮含量的氧化层,更能有效的去抵挡硼的扩散。形成此含氮氧化层有三步骤,首先把晶片浸泡于双氧水中,形成化学氧化层,接着在低压的环境下用氨气去执行氮化,最后通氧气用来执行再氧化动作。经过以上三各步骤,就可以在介面上形成高氮含量的氧化层,此法制程简单而且跟目前的制程技术是相容的。
   最后,我们会把此含氮氧化层应用在N型电晶体上,再来探讨N型电晶体的电性和可靠度,都拥有低的漏电和对于施加高电场应力有好的忍耐度,且有强的抵抗硼扩散能力和抵抗热载子能力。
Abstract
According to the scaling rules, aggressive scaling has lead to silicon dioxide (SiO2) gate dielectrics as ultra thin in state-of-the-art CMOS technologies. As a consequence, static leakage current due to direct tunneling through the gate oxide has been increasing at an exponential rate. As technology roadmaps call for sub-10A° gate oxides within the next five years, a variety of alternative high-k materials are being investigated as possible replacements for SiO2. The higher dielectric constants in these materials allow the use of physically thicker films, potentially reducing the tunneling current while maintaining the gate capacitance needed for scaled device operation.
Oxynitride(SiON) have been reported to show many advantages over thermal oxide.For example,excellent resistance to penetration of dopant and other impurities such
as refractory metal,a higher dielectric strength,and enhanced resistance to damage
induced by radiation and high-field stress . As the continuing scaling down of MOS devices has made high-field-induced device degradation a major concern,thin oxynitride seem promising for applications as a replacement for a thermally grown
oxide in submicrometer-range ULSI devices.
The oxynitrides with high nitrogen content distributed close to the surface are considered to be the best candidates for 65 nm CMOS integration or below. We propose an alternative approach for forming a high-nitrogen ultrathin oxynitride gate dielectric is demonstrated. The oxynitride growth included three process stages-chemical oxide growth, nitridation and subsequent dry oxidation. Meanwhile, chemical oxide as a starting oxide can provide a better controllability in film thickness. Following that, the chemical oxide was nitrided using a furnace in low-pressure NH3 ambient to transfer high-nitrogen oxynitride. The nitrided chemical oxide was then placed in atmospheric O2 ambient to form a robust oxynitride. The process proposed here is simple and fully compatible with current process technology.
Finally, by this technique, nMOSFET of oxynitride were fabricated to study electrical characteristics. They demonstrate excellent properties in terms of low leakage current, high endurance in stressing, superior boron diffusion blocking behavior and weak SILC effect, and good performance in HCI effect.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT009411581
http://hdl.handle.net/11536/80496
显示于类别:Thesis


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  1. 158101.pdf
  2. 158102.pdf
  3. 158103.pdf
  4. 158104.pdf
  5. 158105.pdf
  6. 158106.pdf
  7. 158107.pdf
  8. 158108.pdf
  9. 158109.pdf
  10. 158110.pdf

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