公开(公告)号：US06211010B1

公开(公告)日：2001-04-03

申请号：US09451842

申请日：1999-12-01

申请人： Jang Hyeok Lee ,  Se Hyoung Ryu ,  Chan Sik Park ,  Eung Yong Ahn ,  Yun Young Kwon

发明人： Jang Hyeok Lee ,  Se Hyoung Ryu ,  Chan Sik Park ,  Eung Yong Ahn ,  Yun Young Kwon

IPC分类号： H01L218242

CPC分类号： H01L28/84 ,  H01L21/02052 ,  H01L21/31116 ,  H01L21/32136 ,  H01L27/10852

摘要： A method of forming a hemispherical grain includes cleaning a polysilicon layer of a native oxide in-situ in the processing chamber of the HSG growth reactor. Such a native oxide adversely affects the growing of HSGs from seeds during the thermal treatment performed in the processing chamber. The cleaning is carried out by dry etching the polysilicon layer with plasma. The plasma may be produced from a mixture of fluorine and inert gases having a volumetric ratio within the range of 0.2:100 to 25:100. Such a plasma can be formed by ionizing the gas with an RF power within a range of 20 to 500 Watts. An advantage of using plasma etching to clean the polysilicon of a native oxide is that the plasma etching is an anisotropic process. The present invention is thus particularly useful in the manufacture of a DRAM capacitor. In such a case, the hemispherical grains at neighboring side walls of the DRAM capacitor have a smaller average grain size than that of the hemispherical grains at the upper surfaces of the capacitor. The smaller HSGs are less likely to bridge, and yet the capacitor may still have some comparatively large grains contributing to the increased capacitance provided by the HSGs.

摘要翻译： 形成半球形颗粒的方法包括在HSG生长反应器的处理室中原位清洁天然氧化物的多晶硅层。 这种天然氧化物在处理室中进行的热处理期间不利地影响来自种子的HSG的生长。 通过用等离子体干蚀刻多晶硅层来进行清洗。 等离子体可以由体积比在0.2:100至25:100范围内的氟和惰性气体的混合物产生。 这样的等离子体可以通过以20〜500瓦的范围内的RF功率电离气体来形成。 使用等离子体蚀刻来清洁天然氧化物的多晶硅的优点是等离子体蚀刻是各向异性工艺。 因此，本发明在DRAM电容器的制造中特别有用。 在这种情况下，DRAM电容器的相邻侧壁处的半球状晶粒的平均粒径比电容器上表面的半球状晶粒小。 较小的HSG不太可能桥接，然而电容器可能仍然具有一些比较大的晶粒，这有助于HSG提供的增加的电容。