本文選題：氮化鎵 + 高分辨三軸X射線衍射　； 參考：《物理學(xué)報(bào)》2017年21期

【摘要】：三軸X射線衍射技術(shù)廣泛應(yīng)用于半導(dǎo)體材料參數(shù)的精確測(cè)試,然而應(yīng)用于纖鋅礦n-GaN位錯(cuò)密度的測(cè)試卻可能隱藏極大的誤差.本文采用三軸X射線衍射技術(shù)測(cè)試了兩個(gè)氫化物氣相外延方法生長(zhǎng)的n-GaN樣品,發(fā)現(xiàn)兩樣品對(duì)應(yīng)衍射面的半高全寬都基本一致,按照鑲嵌結(jié)構(gòu)模型,采用Srikant方法或Williamson-Hall方法,兩樣品的位錯(cuò)密度也應(yīng)基本一致.但van der Pauw變溫霍爾效應(yīng)測(cè)試表明,其中的非故意摻雜樣品是莫特相變材料,而摻Si樣品則是非莫特相變材料,位錯(cuò)密度有數(shù)量級(jí)的差別.實(shí)驗(yàn)表明,位錯(cuò)沿晶界生長(zhǎng)導(dǎo)致的晶粒尺寸效應(yīng),表現(xiàn)為三軸X射線衍射技術(shù)檢測(cè)不到晶界晶格畸變區(qū)域的位錯(cuò),給測(cè)試帶來(lái)極大誤差,這對(duì)正確使用Srikant方法和Williamson-Hall方法提出了測(cè)試要求.分析表明,當(dāng)扭轉(zhuǎn)角與傾轉(zhuǎn)角之比β_(twist)/β_(tiit)≥2.0時(shí),Srikant方法是準(zhǔn)確的,否則需進(jìn)一步由Williamson-Hall方法確定晶粒大小(面內(nèi)共格長(zhǎng)度L//),當(dāng)L//≥1.5μm時(shí),Srikant方法是準(zhǔn)確的.
[Abstract]:Triaxial X-ray diffraction technique is widely used in the accurate measurement of semiconductor material parameters, however, the measurement of dislocation density of wurtzite n-GaN may conceal great errors. In this paper, the n-GaN samples grown by two hydride vapor phase epitaxy methods have been measured by using triaxial X-ray diffraction technique. It is found that the half height full width of the corresponding diffraction surfaces of the two samples are basically the same. According to the mosaic structure model, the Srikant method or Williamson-Hall method is used. The dislocation density of the two samples should be basically the same. However, the van der Pauw variable-temperature Hall effect test shows that the unintentionally doped sample is a Mott phase change material, while the Si doped sample is a non-Mott phase change material, and the dislocation density varies by an order of magnitude. The experimental results show that the grain size effect caused by the growth of dislocations along grain boundaries is characterized by triaxial X-ray diffraction, which can not detect the dislocation in the lattice distortion region of grain boundaries, which brings great error to the measurement. This puts forward the test requirements for the correct use of the Srikant method and the Williamson-Hall method. The analysis shows that the Srikant method is accurate when the ratio of torsion angle to tilting angle 尾 is greater than 2.0, otherwise it is necessary to determine the grain size by the Williamson-Hall method (the in-plane coherent length L / R), and the Srikant method is accurate when L / L / 鈮，

本文編號(hào)：1903932