Fabrication of UV-Sensitive SiC Diode by Laser Processing

通过激光加工制造紫外敏感碳化硅二极管

基本信息

批准号：
11450121
负责人：
NAKASHIMA Kentare
金额：
$ 9.22万
依托单位：
Nagoya 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：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450121/
关键词：
Silicon carbide excimer laser laser doping UV sensor Photo-responsivity aluminum Titanium ohmic contact エキシマレーザーレーザー・プロセス W タングステン

项目摘要

(1) Results in 1999(a) Al-depth profiles in n-type 6H-SiC doped with a pulsed excimer laser (KrF) processing method under the conditions of a constant pressure 100 Torr of the hydrogen-diluted TMA (trimethylaluminum) have been evaluated varying a number of laser pulses from 1000 to 8000 shots. They were approximated as sum of two complimentary error-functions ; the one nearer to surface ranging from 10 to 30 nm and the other inner one (tail distribution) from 20 to 100 nm. The investigations show that the aluminum depth profiles could be controlled between 20 and 100 nm according to the number of the laser pulses. A fraction of doped Al was electrically activated without any post heat treatments, and p-type conduction was confirmed with Hall effect and I-V measurements. Al-acceptor levels at E_v+0.239 eV was also confirmed with PL measurements.(b) Ohmic contacts with W/Ti and Al/Ti to n- and p-type 6H-SiC substrates, respectively, have been refined with a pulsed laser processing using … More KrF excimer laser. The electrodes have very smooth surfaces and the contact resistivity of 6.7x10^<-5> and 1x10^<-3> Ωcm^2 for n- and p-type substrate, respectively. The contact interface regions are very thin comparing with the one produced with heat treatments at high temperature.(2) Results in 2000(a) Al-depth profiles in n-type 6H-SiC doped with a pulsed laser processing using a KrF excimer laser have reconfirmed the distribution of the both regions of 0 to 20 nm and 20 to 100 nm, which are approximated with the sum of the complimentary error-function. The surface Al concentrations estimated from the curve fitting are 9.0x10^<17>, 4.5x10^<18>, and 2.7x10^<19> Al/cm^3 for the respective gas pressure of TMA/H_2 10, 100, and 200 Torr, keeping constant an energy density of the laser pulse 1.2J/cm^2 and a number of laser shots 1000. The present investigations confirmed that Al-depth profiles could be controlled with three parameters such as the TMA/H_2 gas pressure and the laser energy density, and a number of laser shots.(b) Thin pn junction diodes have been fabricated on the undoped n-type 6H-SiC (2.5x10^<115> N/cm^3) under the following conditions, TMA/H_2 ; 100 Torr, No.of shots ; 8000, and 1.2J/cm^2. Using a thin Al/Ti ohmic contact on the P-type doped-layer, the photo-responsivity has maximum external quantum efficiency 41% at the wavelength of 330 nm. Less

(1) 1999年的结果(a) 采用脉冲准分子激光(KrF)加工方法掺杂的n型6H-SiC在氢稀释TMA(三甲基铝)恒压100Torr的条件下Al深度分布有对 1000 到 8000 次发射的激光脉冲进行了评估，它们被近似为两个更接近的误差函数的总和；表面范围为 10 至 30 nm，另一个内部（尾部分布）范围为 20 至 100 nm。结果表明，根据激光研究脉冲的数量，可以将铝深度分布控制在 20 至 100 nm 之间。掺杂的 Al 在没有任何后热处理的情况下被电激活，并且通过霍尔效应证实了 p 型传导，并且还通过 E_v+0.239 eV 的 I-V 测量证实了 Al 受体水平。 PL 测量。(b) W/Ti 和 Al/Ti 分别与 n 型和 p 型 6H-SiC 基板的欧姆接触已使用 KrF 准分子激光器通过脉冲激光加工进行了细化。电极具有非常光滑的特性。 n 型和 p 型衬底的接触电阻率分别为 6.7x10^<-5> 和 1x10^<-3> Ωcm^2 与（2）2000年的结果（a）使用KrF准分子激光器进行脉冲激光加工的n型6H-SiC掺杂的Al深度剖面再次证实了两个0区域的分布至 20 nm 和 20 至 100 nm，它们是用互补误差函数之和近似的。从曲线拟合估计的表面 Al 浓度为对于 TMA/H_2 10、100 和 200 Torr 的相应气压，保持能量密度恒定，分别为 9.0x10^<17>、4.5x10^<18> 和 2.7x10^<19> Al/cm^3激光脉冲 1.2J/cm^2 和激光发射次数 1000。目前的研究证实，Al 深度剖面可以通过三个参数控制例如TMA/H_2气体压力和激光能量密度，以及激光发射次数。(b)在未掺杂的n型6H-SiC (2.5x10^<115> N/cm)上制备了薄pn结二极管^3) 在以下条件下，TMA/H_2；100 Torr，射数 8000，和 1.2J/cm^2。 P型掺杂层上的Al/Ti欧姆接触，在波长330 nm处具有最大外量子效率41%以下。