Position control of InAs quantum dots by using AFM oxidation method and application to single electron transistor

近年来，通过对半导体超精细加工技术的改进，积极研究开发量子效应的器件，如单电子晶体管（SETs）。近年来，利用材料组成原子晶格常数的不同而产生的畸变，实现详细结构的自形成的特殊“自组织”现象，作为加工技术与利用离子束、电子束等手段生产这些器件的超精细加工技术的补充，非常受到人们的关注。然而，InAs量子点（QDs）必须对每个进行自组织生长的量子点进行位置控制，才能实现大量的随机生长，并适用于单电子器件。然后，在本研究中，着眼于在单电子器件上的应用，并利用我们目前开发的原子力显微镜（AFM）进行阳极氧化的技术。首先，采用分子束外延（MBE）方法培养InAs量子点，降低量子点密度并进行迁移试验。在InAs量子点生长的状态下，密度下降比衬底温度提高了40 ~ 70度。它已经计算出，当量子点理论上迁移，点连接在一起或蒸发时，密度会降低。接下来，通过AFM氧化在GaAs衬底上进行详细处理，制备纳米模板，生长InAs量子点并在其上进行原位退火，尝试了InAs量子点的位置控制。因此，研究了InAs量子点向原位退火迁移后经AFM氧化处理的纳米空穴移动的现象。

In recent years the Research, which is going to develop the quantum effect, devices, such as single electronic transistors (SETs), is actively made by improvement in semiconductor ultra-fine processing technology. The specific "self-organization" phenomenon which carries out self-formation of the detailed structure very much attracts attention by distortion by the difference in the lattice constant of a material composition atom in recent years as processing technology which complements the ultra-fine processing technology using the ion beam, the electronic beam, etc. as a means to produce those devices.However, InAs quantum dots (QDs) has indispensable position contrl of each dots which carried out self-organization growth, in order for a large number to grow at rapdom, and apply to a single electron device. Then, in this research, it gazed at the application to a single electron device, and the technique of performing anode oxidization using the atomic force microscope (AFM) which we have developed by present was used.First, InAs QDs were grown up by using molecular beam epitaxy (MBE) method, and QD's density is decreased and migration was tried. Decreased density was raised by 40 degrees to 70 degrees from the substrate temperature in the state where the InAs QDs was grown up. It has figured out that decreased density, when the QDs migrated theoretically and dots join together or evaporated.Next, position control of InAs QDs were tried by performing detailed processing on a GaAs substrate by using the AFM oxidation, producing a nano-template, growing up InAs QDs and carrying out in-situ annealing on it.Consequently, the phenomenon which an InAs quantum dot moves to the nano-hole which migrated by in-situ annealing, and which was processed by the AFM oxidation has been figured out.