Surface segregation is studied via the evolution of reflection high-energy electron diffraction （RHEED） patterns under different values of As4 BEP for InGaAs films. When the As4 BEP is set to be zero, the RHEED patt...Surface segregation is studied via the evolution of reflection high-energy electron diffraction （RHEED） patterns under different values of As4 BEP for InGaAs films. When the As4 BEP is set to be zero, the RHEED pattern keeps a 4x3/（nx3） structure with increasing temperature, and surface segregation takes place until 470 ℃ The RHEED pattern develops into a metal-rich （4x2） structure as temperature increases to 495℃. The reason for this is that surface segregation makes the In inside the InGaAs film climb to its surface. With the temperature increasing up to 515℃, the RHEED pattern turns into a GaAs（2x4） structure due to In desorption. While the As4 BEP comes up to a specific value （1.33 x 10-4 Pa-1.33 x 10-3 Pa）, the surface temperature can delay the segregation and desorption. We find that As4 BEP has a big influence on surface desorption, while surface segregation is more strongly dependent on temperature than surface desorption.展开更多
The present paper discusses our investigation of InGaAs surface morphology annealed for different lengths of time.After annealing for 15 min,the ripening of InGaAs islands is completed.The real space scanning tunnelin...The present paper discusses our investigation of InGaAs surface morphology annealed for different lengths of time.After annealing for 15 min,the ripening of InGaAs islands is completed.The real space scanning tunneling microscopy（STM） images show the evolution of InGaAs surface morphology.A half-terrace diffusion theoretical model based on thermodynamic theory is proposed to estimate the annealing time for obtaining flat morphology.The annealing time calculated by the proposed theory is in agreement with the experimental results.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 60866001)the Special Assistant to High-Level Personnel Research Projects of Guizhou Provincial Party Committee Organization Department of China (Grant No. TZJF- 2008-31)+3 种基金the Support Plan of New Century Excellent Talents of Ministry of Education, China (Grant No. NCET-08-0651)the Doctorate Foundation of the State Education Ministry of China (Grant No. 20105201110003)the Special Governor Fund of Outstanding Professionals in Science and Technology and Education of Guizhou Province, China (Grant No. 2009114)the Doctoral Foundation Projects of Guizhou College of Finance and Economics in 2010
文摘Surface segregation is studied via the evolution of reflection high-energy electron diffraction （RHEED） patterns under different values of As4 BEP for InGaAs films. When the As4 BEP is set to be zero, the RHEED pattern keeps a 4x3/（nx3） structure with increasing temperature, and surface segregation takes place until 470 ℃ The RHEED pattern develops into a metal-rich （4x2） structure as temperature increases to 495℃. The reason for this is that surface segregation makes the In inside the InGaAs film climb to its surface. With the temperature increasing up to 515℃, the RHEED pattern turns into a GaAs（2x4） structure due to In desorption. While the As4 BEP comes up to a specific value （1.33 x 10-4 Pa-1.33 x 10-3 Pa）, the surface temperature can delay the segregation and desorption. We find that As4 BEP has a big influence on surface desorption, while surface segregation is more strongly dependent on temperature than surface desorption.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60866001 and 61076049)the Science and Technology Projects for Overseas Researchers of Guizhou Province (Grant No. (2007) 03)+5 种基金the Foundation of Guizhou Provincial Science and Technology Department (Grant No. QKH-J[2007]2176)the Special Assistant to the High-Level Personnel Research Projects of Guizhou Provincial Committee,Organization Department(Grant No. TZJF-200610)the Doctorate Foundation of the Education Ministry of China (Grant No. 20105201110003)the Science and Technology Projects for Overseas Researchers of Guizhou Province (Grant No. Z103233)Special Governor Fund for Outstanding Professionals in Science & Technology and Education of Guizhou Province (Grant No. 2009114)the Innovation Funds for Graduates of Guizhou University (Grant No. LG2012019)
文摘The present paper discusses our investigation of InGaAs surface morphology annealed for different lengths of time.After annealing for 15 min,the ripening of InGaAs islands is completed.The real space scanning tunneling microscopy（STM） images show the evolution of InGaAs surface morphology.A half-terrace diffusion theoretical model based on thermodynamic theory is proposed to estimate the annealing time for obtaining flat morphology.The annealing time calculated by the proposed theory is in agreement with the experimental results.
