Preparation of ferroelectric BaMgF_4films on GaAs for the control of two-dimensional electron gas

GaAs上铁电BaMgF_4薄膜的制备用于二维电子气控制

基本信息

批准号：
07455134
负责人：
TOKUMITSU Eisuke
金额：
$ 3.46万
依托单位：
TOKYO 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：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07455134/
关键词：
ferroelectric thin film GaAs BaMgF_4 high electron mobility transistor (HEMT)two dimensional electron gas moleculat beam epitaxy (MBE)

项目摘要

In this project, we have proposed a new device, ferroelectric-gate high electron mobility transistor (F-HEMT), in which two dimensional electron gas (2DEG) can be controlled by the polarization of the ferroelectric film. In order to realize the device, we have investigated the growth of ferroelectric BaMgF_4 thin films on AlGaAs/GaAs HEMT structures using molecular beam epitaxy (MBE). An MBE system used in this project consists of a road-rock chamber and two growth chambers, where one is used for Ga (Al) As growth and the other for BaMgF_4 growht. First, we have shown that the (140) -oriented BaMgF_4 films can be grown on GaAs substrates above 500ﾟC.However, it has been found that electron mobility of 2DEG decreases when the BaMgF_4 film is grown above 600ﾟC,because of the inter-diffusion of the constituent elements. In addition, 2-step growth method has been proposed to grow high quality BaMgF_4 films, where the thin (140) -oriented BaMgF_4 layr is grown at 550ﾟC for a short time followed by the low temperature (300ﾟC) growth of amorphous BaMgF_4 films. Good ferroelectric properties and sharp interfaces have been obtained by annealing the BaMgF_4 films grown by the 2-step method. We have also studied the dry etching of BaMgF_4 thin films using Ar/Cl_2 as etching gases and found that the etching damage is less serious for the film etched by dry-etching process than by the normal wet chemical etching. Finally, we have fabricated BaMgF_4/AlGaAs/GaAs F-HEMTs for the first time and shown that the device has proper transistro characteristics with non-volatile memory function because of the ferroelectric nature of the BaMgF_4 film.

在这个项目中，我们提出了一种新设备，即铁栅极高电子迁移式晶体管（F-HEMT），其中二维电子气体（2DEG）可以通过铁电膜的极化来控制。为了实现该设备，我们研究了使用分子束外延（MBE）在藻类/GAAS HEMT结构上的铁电BAMGF_4薄膜的生长。该项目中使用的MBE系统由一个路 - 摇滚室和两个生长室组成，其中一个用于GA（Al），另一个用于BAMGF_4 growht。首先，我们已经表明，（140）面向的BAMGF_4胶片可以在500℃以上的GAAS底物上生长。此外，已经提出了两步增长方法来生长高质量的BAMGF_4膜，其中薄（140）面向面向的BAMGF_4 Layr在短时间内在550℃下生长，然后在低温（300 c）生长的无定形BAMGF_4胶片中生长。通过退火通过2步方法退火，已经获得了良好的铁电特性和锋利的界面。我们还使用AR/CL_2作为蚀刻气体研究了BAMGF_4薄膜的干燥蚀刻，发现蚀刻损伤对被干蚀刻过程所擦除的膜不如正常的湿化学蚀刻而严重。最后，我们首次制造了BAMGF_4/Algaas/gaas f-Hemts，并表明该设备具有适当的跨膜特性特征，具有非挥发性存储器功能，因为BAMGF_4膜的铁电性性质。