Study on the Fundamental Mechanism of Radical Beam Epitaxy

该研究程序的目标是开发一种新的外延增长技术，用于使用一种由直流发光放电或电子回旋加速器共振（ECR）等离子体产生的低外延温度的基础光束。如需在较低温度下使用精硅同源物，并将低温度表面清洁优先者清除到表面生长，SiH_X基片的中性片段由SiH_4的电荷分解产生，可用于满足c-Si （100）基底，并将SiH_X基片放置在超高真空室。结果大致如下：（1）硅外延层在温度低于550 ° C的情况下生长，由利用15%SiH_4稀释的直流电产生的激进光束产生的发光二极管发光放电。（2）当氢基分子的明显光束强度在生长表面上受到辐射时，其基本温度下降到520 ° C是在表面上静止去除氧离子浓度的结果。在辐照过氢基束的情况下，双晶体或多晶体管形成了表面硅束的过度氢化，因为硅网络的表面硅束相互作用。由于低氢束强度，氧的感染不能被有效地去除，并且Hence多分泌蛋白相位出现。（3）SiH_X radical beam irradiation reduce the epitxial temperature to 400 C presumably because ECR plasma effectively creates highly excited SiH_X radicals。（4） Irradiation of a suitable amount of SiH_X radicals from SiH_4 ECR plasma is quite beneficial remove the thin protective oxide formed on the substrate surface。在基础光束清洁技术下，硅表面获得了650 ° C的温度。

The objective of this research program is to develop a new epitaxial growth technique for lowering the epitaxial temperature by using a radical beam produced with a dc glow discharge or electron cyclotron resonance (ECR) plasma of a material gas. In order to obtain the fine silicon homoepitaxy at lower temperature and to realize low temperature surface cleaning prior to the epitaxial growth, neutral fragment of SiH_X radicals created by the discharge decomposition of SiH_4 are effused onto a c-Si (100) substrate placed on a ultra-high vacuum chamber. The results are summarized as follows:(1) Silicon epitaxial layers have been grown at temperatures as low as 550 ゜C by using a radical beam produced by the dc glow discharge of 15 % SiH_4 diluted with Ar. (2) When an adequate beam intensity of hydrogen radicals is irradiated on the growing surface, the epitaxial temperature is lowered down to 520 ゜C as a result of in situ removal of oxygen contamination on the surface. In case of irradiating the excess hydrogen radical beam, twin crystal or polycrystalline is formed because the overhydrogenation of surface silicon bonds interrupts the silicon network formation. For a low hydrogen beam intensity, oxygen contamination can not be effectively removed and hence polycrystalline phase appears. (3) SiH_X radical beam irradiation reduce the epitxial temperature to 400 ゜C presumably because ECR plasma effectively creates highly excited SiH_X radicals. (4) Irradiation of a suitable amount of SiH_X radicals from SiH_4 ECR plasma is quite beneficial remove the thin protective oxide formed on the substrate surface. Consequently clean Si surface is obtained at a temperature of 650 ゜C by the radical beam cleaning technique.