We report a type-Ⅱ InAs/GaSb superlattice three-color infrared detector for mid-wave （MW）, long-wave （LW）, and very long-wave （VLW） detections. The detector structure consists of three contacts of NIPIN archite...We report a type-Ⅱ InAs/GaSb superlattice three-color infrared detector for mid-wave （MW）, long-wave （LW）, and very long-wave （VLW） detections. The detector structure consists of three contacts of NIPIN architecture for MW and LW detections, and hetero-junction NIP architecture for VLW detection. It is found that the spectral crosstalks can be significantly reduced by controlling the minority carriers transport via doping beryllium in the two active regions of NIPIN section. The crosstalk detection at MW, LW, and VLW signals are achieved by selecting the bias voltages on the device. At 77K, the cutoff wavelengths of the three-color detection are 5.3μm （at OmV）, 141μm （at 300mV） and 19μm （at -20mV） with the detectivities of 4.6xlO11 cm.Hzl/ZW-1, 2.3×10^10 cm.Hzl/2W-1, and 1.0×10^10cm.Hzl/2W-1 for MW, LW and VLW. The crosstalks of the MW channel, LW channel, and VLW channel are almost 0, 0.25, and 0.6, respectively.展开更多
Black phosphorus(BP)has been shown as a promising two-dimensional(2D)material for electronic devices owing to its high carrier mobility.To realize complementary electronic circuits with 2D materials,it is important to...Black phosphorus(BP)has been shown as a promising two-dimensional(2D)material for electronic devices owing to its high carrier mobility.To realize complementary electronic circuits with 2D materials,it is important to fabricate both n-type and p-type transistors with the same channel material.By engineering the contact region with copper(Cu)-doped BP,here we demonstrate an n-type carrier transport in BP field-effect transistors(FETs),which usually exhibit strongly p-type characteristics.Cu metal atoms are found to severely penetrate into the BP flakes,which forms interstitial Cu(Cuint)-doped edge contact and facilitates the electron transport in BP.Our BP FETs in backgated configuration exhibit n-type dominant characteristics with a high electron mobility of^138 cm^2 V^−1 s^−1 at room temperature.The Schottky barrier height for electrons is relatively low because of the edge contact between Cuint-doped BP and pristine BP channel.The contact doping of BP by highly mobile Cu atoms gives rise to n-type transport property of BP FETs.Furthermore,we demonstrate a p-n junction on the same BP flake with asymmetric contact.This strategy on contact engineering can be further extended to other 2D materials.展开更多
Van der Waals semiconductor heterostructures(VSHs)composed of two or more two-dimensional(2D)materials with different band gaps exhibit huge potential for exploiting high-performance multifunctional devices.The applic...Van der Waals semiconductor heterostructures(VSHs)composed of two or more two-dimensional(2D)materials with different band gaps exhibit huge potential for exploiting high-performance multifunctional devices.The application of 2D VSHs in atomically thin devices highly depends on the control of their carrier type and density.Herein,on the basis of comprehensive first-principles calculations,we report a new strategy to manipulate the doping polarity and carrier density in a class of 2D VSHs consisting of atomically thin transition metal dichalcogenides(TMDs)andα-In_(2)X_(3)(X=S,Se)ferroelectrics via switchable polarization field.Our calculated results indicate that the band bending of In_(2)X_(3)layer driven by the FE polarization can be utilized for engineering the band alignment and doping polarity of TMD/In_(2)X_(3)VSHs,which enables us to control their carrier density and type of the VSHs by the orientation and magnitude of local FE polarization field.Inspired by these findings,we demonstrate that doping-free p–n junctions achieved in MoTe2/In2Se3 VSHs exhibit high carrier density(1013–1014 cm–2),and the inversion of the VHSs from n–p junctions to p–i–n junctions has been realized by the polarization switching from upward to downward states.This work provides a nonvolatile and nondestructive doping strategy for obtaining programmable p–n van der Waals(vdW)junctions and opens the possibilities for self-powered and multifunctional device applications.展开更多
基金Supported by the National Basic Research Program of China under Grant Nos 2014CB643903,2013CB932904,2012CB932701 and 2011CB922201the National Special Funds for the Development of Major Research Equipment and Instruments of China under Grant No 2012YQ140005+7 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences under Grant No XDB01010200the China Postdoctoral Science Foundation-funded Project under Grant No 2014M561029the Program for New Century Excellent Talents in University under Grant No NCET-10-0066the National High-Technology Research and Development Program of China under Grant No 2013AA031502the Science and Technology Innovation Project of Harbin City under Grant No2011RFLXG006the National Natural Science Foundation of China under Grant Nos 61274013,U1037602,61306013,51202046,and 61290303the China Postdoctoral Science Foundation under Grant Nos 2012M510144 and 2013T60366the Fundamental Research Funds for the Central Universities under Grant Nos HIT.NSRIF.2013006 and HIT.BRETIII.201403
文摘We report a type-Ⅱ InAs/GaSb superlattice three-color infrared detector for mid-wave （MW）, long-wave （LW）, and very long-wave （VLW） detections. The detector structure consists of three contacts of NIPIN architecture for MW and LW detections, and hetero-junction NIP architecture for VLW detection. It is found that the spectral crosstalks can be significantly reduced by controlling the minority carriers transport via doping beryllium in the two active regions of NIPIN section. The crosstalk detection at MW, LW, and VLW signals are achieved by selecting the bias voltages on the device. At 77K, the cutoff wavelengths of the three-color detection are 5.3μm （at OmV）, 141μm （at 300mV） and 19μm （at -20mV） with the detectivities of 4.6xlO11 cm.Hzl/ZW-1, 2.3×10^10 cm.Hzl/2W-1, and 1.0×10^10cm.Hzl/2W-1 for MW, LW and VLW. The crosstalks of the MW channel, LW channel, and VLW channel are almost 0, 0.25, and 0.6, respectively.
基金supported by the Research Grant Council of Hong Kong(PolyU 152145/15E and 15305718)the Hong Kong Polytechnic University(G-YBPS,G-SB79 and 1-ZE6G)X.G.and Y.Z.thank Dr.Wei Lu for optimizing the JEOL JEM-2100F microscope.
文摘Black phosphorus(BP)has been shown as a promising two-dimensional(2D)material for electronic devices owing to its high carrier mobility.To realize complementary electronic circuits with 2D materials,it is important to fabricate both n-type and p-type transistors with the same channel material.By engineering the contact region with copper(Cu)-doped BP,here we demonstrate an n-type carrier transport in BP field-effect transistors(FETs),which usually exhibit strongly p-type characteristics.Cu metal atoms are found to severely penetrate into the BP flakes,which forms interstitial Cu(Cuint)-doped edge contact and facilitates the electron transport in BP.Our BP FETs in backgated configuration exhibit n-type dominant characteristics with a high electron mobility of^138 cm^2 V^−1 s^−1 at room temperature.The Schottky barrier height for electrons is relatively low because of the edge contact between Cuint-doped BP and pristine BP channel.The contact doping of BP by highly mobile Cu atoms gives rise to n-type transport property of BP FETs.Furthermore,we demonstrate a p-n junction on the same BP flake with asymmetric contact.This strategy on contact engineering can be further extended to other 2D materials.
基金supported by the National Natural Science Foundation of China(Grant No.62174151 and 61775201)the Fund of Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ22F040003 and LY22A040002).
文摘Van der Waals semiconductor heterostructures(VSHs)composed of two or more two-dimensional(2D)materials with different band gaps exhibit huge potential for exploiting high-performance multifunctional devices.The application of 2D VSHs in atomically thin devices highly depends on the control of their carrier type and density.Herein,on the basis of comprehensive first-principles calculations,we report a new strategy to manipulate the doping polarity and carrier density in a class of 2D VSHs consisting of atomically thin transition metal dichalcogenides(TMDs)andα-In_(2)X_(3)(X=S,Se)ferroelectrics via switchable polarization field.Our calculated results indicate that the band bending of In_(2)X_(3)layer driven by the FE polarization can be utilized for engineering the band alignment and doping polarity of TMD/In_(2)X_(3)VSHs,which enables us to control their carrier density and type of the VSHs by the orientation and magnitude of local FE polarization field.Inspired by these findings,we demonstrate that doping-free p–n junctions achieved in MoTe2/In2Se3 VSHs exhibit high carrier density(1013–1014 cm–2),and the inversion of the VHSs from n–p junctions to p–i–n junctions has been realized by the polarization switching from upward to downward states.This work provides a nonvolatile and nondestructive doping strategy for obtaining programmable p–n van der Waals(vdW)junctions and opens the possibilities for self-powered and multifunctional device applications.
