Growth condition optimization and mobility enhancement through inserting AlAs monolayer in the InP-based In_xGa_1-xAs/In_0.52Al_0.48As HEMT structures

【摘要】 The structure of In P-based In_xGa_1-x As/In0.52Al0.48 As pseudomorphic high electron mobility transistor（PHEMT）was optimized in detail.Effects of growth temperature,growth interruption time,Si δ-doping condition,channel thickness and In content,and inserted Al As monolayer（ML） on the two-dimensional electron gas（2DEG） performance were investigated carefully.It was found that the use of the inserted Al As monolayer has an enhancement effect on the mobility due to the reduction of interface roughness and the suppression of Si movement.With optimization of the growth parameters,the structures composed of a 10 nm thick In0.75Ga0.25 As channel layer and a 3 nm thick Al As/In0.52Al0.48 As superlattices spacer layer exhibited electron mobilities as high as 12500 cm²·V-1·s^-1（300 K） and 53500 cm²·V⁽-1_·s^-1（77 K） and the corresponding sheet carrier concentrations（Ns） of 2.8×10¹²cm^-2and 2.9×1012cm^-2,respectively.To the best of the authors’ knowledge,this is the highest reported room temperature mobility for In P-based HEMTs with a spacer of 3 nm to date.更多还原

【Abstract】 The structure of In P-based In_xGa_1-x As/In0.52Al0.48 As pseudomorphic high electron mobility transistor（PHEMT）was optimized in detail.Effects of growth temperature,growth interruption time,Si δ-doping condition,channel thickness and In content,and inserted Al As monolayer（ML） on the two-dimensional electron gas（2DEG） performance were investigated carefully.It was found that the use of the inserted Al As monolayer has an enhancement effect on the mobility due to the reduction of interface roughness and the suppression of Si movement.With optimization of the growth parameters,the structures composed of a 10 nm thick In0.75Ga0.25 As channel layer and a 3 nm thick Al As/In0.52Al0.48 As superlattices spacer layer exhibited electron mobilities as high as 12500 cm²·V-1·s^-1（300 K） and 53500 cm²·V⁽-1_·s^-1（77 K） and the corresponding sheet carrier concentrations（Ns） of 2.8×10¹²cm^-2and 2.9×1012cm^-2,respectively.To the best of the authors’ knowledge,this is the highest reported room temperature mobility for In P-based HEMTs with a spacer of 3 nm to date.更多还原