INVESTIGATION ON ELECTRONIC CHARACTERISTICS OF SiGe MULTI-QUANTUM WELL CHANNEL MOSFETs ON A SOI SUBSTRATE

SOI 衬底上 SiGe 多量子阱沟道 MOSFET 的电子特性研究

• 批准号: 09450145
• 负责人: FUJINAGA Kiyohisa
• 金额: $ 5.31万
• 依托单位: HOKKAIDO INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-09450145/
• 关键词: silicon; germanium; quantum well; transistor; SOI; MOSFET; CVD; hole current; 電界解効果素子

We had developed a heteroepitaxial chemical vapor deposition apparatus on the basis of ultra-clean technology and grew SiGe quantum wells on a silicon or SOI (Silicon On Insulator) substrate by the apparatus. We verified the physical quality of the wells through TEM, SIMS and photoluminescence measurements and found that the wells were defect-free and the Si/SiGe interfaces were very sharp. The energy levels of the quantum wells agreed with those of the theoretical ones. We grew the 40-nm Si at 550℃ on a SOI substrate (a SIMOX wafer was here used) and fabricated a PMOSFET with the 5.9-nm-thick gate silicon oxide. The I-V characteristics of the device were almost all equal to those for the PMOSFET directly formed on a SIMOX wafer. The results indicated the good precision and accuracy of the epitaxial and device processes. We made SiGe-quantum-well-channel PMOSFETs on a SIMOX wafer (gate Si oxide : 5.9 nm, Si cap layer : 7 nm, Ge fraction of SiGe alloy : 0.2, well width : 13 nm, SOI thickness : 280 nm, Si buffer layer on a SOI wafer : 40 nm). We confirmed the current of holes confined to the SiGe well through the I-V characteristics in the saturation and subthreshold regions. Numerical calculation was carried out for the energy levels and charge densities of heavy holes in single and triple SiGe quantum wells with the Si barrier height of 145 meV.We used 0.266 m_0 as the effective mass of heavy holes in the SiGe layers and 12.6 as the permittivity of the layers. A low hole density below 10^<10> cm^<-3> in the wells was assumed. We clarified the energy levels of the single quantum wells related to the well width and demonstrated the relationship between the energy level or charge density and the Si Barrier width of the triple quantum wells.

我们开发了基于超净技术的异质外延化学气相沉积装置，并利用该装置在硅或SOI（绝缘体上硅）衬底上生长了SiGe量子阱。我们通过 TEM、SIMS 和光致发光测量验证了孔的物理质量，发现孔没有缺陷，Si/SiGe 界面非常锋利。量子阱的能级与理论能级一致。我们在 SOI 衬底（这里使用 SIMOX 晶圆）上于 550℃ 下生长了 40 nm Si，并用 5.9 nm 厚的栅极氧化硅制作了 PMOSFET。该器件的 I-V 特性几乎与直接形成在 SIMOX 晶圆上的 PMOSFET 相同。结果表明外延和器件工艺具有良好的精度和准确度。我们在 SIMOX 晶圆上制作了 SiGe 量子阱沟道 PMOSFET（栅极硅氧化物：5.9 nm，Si 盖层：7 nm，SiGe 合金的 Ge 比例：0.2，阱宽度：13 nm，SOI 厚度：280 nm，SOI 晶圆上的 Si 缓冲层：40 nm）。我们通过饱和区和亚阈值区的 I-V 特性证实了限制在 SiGe 阱中的空穴电流。对SiGe势垒高度为145 meV的单层和三层SiGe量子阱中重空穴的能级和电荷密度进行了数值计算。采用0.266 m_0作为SiGe层中重空穴的有效质量，12.6作为层的介电常数。假设孔中的孔密度低于10^10cm^-3。我们阐明了单量子阱的能级与阱宽度的关系，并论证了三量子阱的能级或电荷密度与Si势垒宽度之间的关系。

项目成果

K.Fujunaga and M.Shibuya: "Numerical calculation for the energy levels and charge densities of heavy holes in SiGe quantum wells.(in Japanese)"Bulletin of Hokkaido Institute of Technology. No.28. 1327-1332 (1997)

K.Fujunaga和M.Shibuya：“SiGe量子阱中重空穴的能级和电荷密度的数值计算。（日语）”北海道工业大学通报。

K.Fujinaga: "MOSFET evaluation of ultracleam-CVD Si and SiGe growm at 550 °C on SIMDX"Chemical Vapor Deposition. (未定). (2000)

K.Fujinaga：“在 SIMDX 上 550 °C 下生长的 Ultracream-CVD Si 和 SiGe 的 MOSFET 评估”化学气相沉积 (TBD)。

K.Fujinaga: "Great reduction of Ge surface contamination in Si/SiGe heteroepitaxy using an ultraclean LPCVD system."The Electrochem.Soc.Proc.. Vol.96-5. 318-323 (1969)

K.Fujinaga：“使用超净 LPCVD 系统大大减少了 Si/SiGe 异质外延中的 Ge 表面污染。”Electrochem.Soc.Proc. 第 96-5 卷。

K.Fujinaga: "MOSFET Evaluation of ultraclean-CVD Si and SiGe grown at 550℃ on SIMOX."The Electrochem.Soc.Proc.. Vol.2000-1(in print). (2000)

K.Fujinaga：“550℃ SIMOX 上生长的超洁净 CVD Si 和 SiGe 的 MOSFET 评估”。Electrochem.Soc.Proc.。Vol.2000-1（印刷中）。

K.Fujinaga: "MOSFET Evaluation of ultraclean-CVD Si and SiGe grown at 550℃ on SIMOX."The 197^<th> Meeting Abstracts of the Electrochem.Soc.No.926, The Electrochem.Soc.Proc.. Vol.2000-1 (in print.). (2000)

K.Fujinaga：“在 SIMOX 上 550℃ 下生长的超洁净 CVD Si 和 SiGe 的 MOSFET 评估”。Electrochem.Soc.No.926 第 197 次会议摘要，Electrochem.Soc.Proc. 卷。 2000-1（印刷中）（2000）。