The pure cubic GaN(c-GaN) has been grown on (001)GaAs substrates by ECR-PAMOCVD technique at low temperature using TMGa and high pure N2 as Ga and N sources, respectively. The effects of substrate pretreatment conditi...The pure cubic GaN(c-GaN) has been grown on (001)GaAs substrates by ECR-PAMOCVD technique at low temperature using TMGa and high pure N2 as Ga and N sources, respectively. The effects of substrate pretreatment conditions on quality of cubic GaN epilayer are investigated by the measurements of TEM and XRD.It is found that hydrogen plasma cleaning, nitridation and buffer layer growth are very important for quality of cubic GaN epilayer.展开更多
The principle of fiber Bragg gratings(FBG) is briefly described. The formation technologies of FBG are systematically given and analyzed. In addition, the experiment is described in detail, e.g.,the phase mask method ...The principle of fiber Bragg gratings(FBG) is briefly described. The formation technologies of FBG are systematically given and analyzed. In addition, the experiment is described in detail, e.g.,the phase mask method is used to write directly the period Bragg gratings into the Ge-doped single mode fiber with KrF excimer UV laser. The results of experiment are also presented and analyzed.展开更多
文摘The pure cubic GaN(c-GaN) has been grown on (001)GaAs substrates by ECR-PAMOCVD technique at low temperature using TMGa and high pure N2 as Ga and N sources, respectively. The effects of substrate pretreatment conditions on quality of cubic GaN epilayer are investigated by the measurements of TEM and XRD.It is found that hydrogen plasma cleaning, nitridation and buffer layer growth are very important for quality of cubic GaN epilayer.
文摘The principle of fiber Bragg gratings(FBG) is briefly described. The formation technologies of FBG are systematically given and analyzed. In addition, the experiment is described in detail, e.g.,the phase mask method is used to write directly the period Bragg gratings into the Ge-doped single mode fiber with KrF excimer UV laser. The results of experiment are also presented and analyzed.
