Polysilanes Doped with Phosphorus by Neutron Transmutation Method

中子嬗变法掺磷聚硅烷

• 批准号: 06640441
• 负责人: MATSUYAMA Tomochika
• 金额: $ 1.15万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640441/
• 关键词: Polysilane; P-Doped polysilane; n-Type semiconductor; Low-dimensional silicon semiconductor; Neutron transmutation doping; Impurity analysis; Number-averabe molecular weight; Neutron activation analysis; 低次元半導体; 低次元系半導体; Polysilane; P-Doped polysilane; n-Type semiconductor; Low-dimensional silicon semiconductor; Neutron transmutation doping; Impurity analysis; Number-averabe molecular weight; Neutron activation analysis; 低次元半導体; 低次元系半導体

If silicon skeleton of polysilane is substitutionally doped with phosphorus, polysilanes become low-dimensional silicon semiconductors with P-impurity. At the present stage, such P-doped polysilanes are available only by means of the neutron transmutation of ^<30>Si. Since the concentration of phosphorus is about 0.1ppm for thermal neutron flux up to 10^<18>/cm^2, the preparation of puriferd polysilanes is an important factor to investigate the physical properties of P-doped polysilanes without perturbation by other impurities.In the present study, we attempted to prepare highly purified polysilanes using the reductive coupling of di-or tri-chlorosilanes with sodium in refluxing toluene. Then a neutron activation method was used in quantitative analysis of impurity traces. It was found that the polysilanes were mainly contaminated by Cl and Na ascribable to the by-product NaCl and the Cl end group in polymers. The content of both impurities in these polymers was distributed in the range of about 10^<-5> to 10^<-1>/monomer unit. Further development of purification procedure is needed for the investigation of the intrinsic properties of P-doped polysilanes. We also studied a scheme to prepare polysilanes doped with phosphorus at much higher level.Quantitative analysis of end group in polymer is valid for determination of its numberaverage molecular weight. Since the polysilanes synthesized above contain Cl end groups, neutron activation analysis of the Cl end groups was applied to determine their numberaverage molecular weight. It was revealed that their molecular weight in some cases go up to 10^7. This fact implies that di-or tri-chlorosilanes are polymerized into extremely high molecular weight polymers. Therefore, if their molecular weight is regulated and their cast films are easily formed, it is expected that we can obtain various polymers with unique properties depending on molecular weight.

如果多硅烷的硅骨架用磷替代掺杂，则多硅烷会成为具有P- IMBRITY的低维硅半导体。目前，这种P掺杂的多硅烷只能通过 ^<30> si的中子变异来获得。由于热中子通量的磷浓度约为10^<18>/cm^2，因此净化puriferd polysilanes的制备是研究p掺杂多硅烷的物理特性而不扰动的重要因素，而没有其他杂质。钠在回流甲苯中。然后将中子激活方法用于杂质痕迹的定量分析。发现多硅烷主要被聚合物中的副产物NaCl和Cl端组污染。这些聚合物中两种杂质的含量分布在约10^<-5>至10^<-1>/单体单元的范围内。需要进一步开发纯化程序来研究P掺杂多硅烷的内在特性。我们还研究了一种在更高级别上掺杂磷的多硅烷的方案。聚合物中末端组的质量分析对于确定其数量的分子量有效。由于上面合成的多硅烷包含Cl端组，因此对Cl端组进行中子激活分析以确定其数量量的分子量。据透露，在某些情况下，它们的分子量高达10^7。这一事实意味着将DI-或三氯硅烷聚合分为极高的分子量聚合物。因此，如果调节它们的分子量并容易形成铸造膜，则可以预期我们可以根据分子量获得具有独特特性的各种聚合物。