本文選題：GaAsBi + 氣態(tài)源分子束外延　； 參考：《材料科學(xué)與工程學(xué)報》2017年03期

【摘要】：為了探究GaAsBi薄膜生長中生長條件與Bi濃度的關(guān)系,我們利用氣態(tài)源分子束外延(GSMBE)技術(shù),通過改變每個GaAsBi單層的生長溫度、AsH_3壓和Bi源溫度,在半絕緣GaAs(100)襯底上生長GaAsBi的多層結(jié)構(gòu)。通過二次離子質(zhì)譜(SIMS)及透射電鏡X光譜(EDX)測試得出:GaAsBi中Bi的濃度隨著生長溫度的升高而降低,且生長速率越慢表面偏析和再蒸發(fā)嚴重,可導(dǎo)致Bi濃度下降趨勢更明顯;Bi濃度隨著AsH_3壓的升高而減小,在As_2和Ga束流比在0.5~0.8之間幾乎成線性變化,遠不如固態(tài)源MBE敏感;此外,Bi源溫度升高,Bi摻入的濃度也會增大,但是當(dāng)生長溫度大于420℃時,Bi就很難凝入。
[Abstract]:In order to investigate the relationship between the growth conditions and Bi concentration in the growth of GaAsBi thin films, we use the gas source molecular beam epitaxy (GMBE) technique. By changing the growth temperature of each GaAsBi monolayer, AsH3 voltage and Bi source temperature, we have grown the multilayer structure of GaAsBi on semi-insulating GaAs / Si (100) substrates. By means of secondary ion mass spectrometry (SIMS) and transmission electron microscopy (TEM) X-ray spectroscopy (EDX), it was found that the concentration of Bi in 1: GaAsBi decreases with the increase of growth temperature, and the slower the growth rate is, the more serious surface segregation and re-evaporation are observed. The decrease trend of Bi concentration is more obvious, and the concentration of Bi decreases with the increase of AsH_3 pressure. The ratio of As_2 to Ga beam is almost linearly changed between 0.5 and 0.8, which is far less sensitive than that of solid-state source MBE, and the concentration of Bi doping increases when the temperature of Bi source increases. However, when the growth temperature is higher than 420 鈩，

本文編號：1853631