用坩埚下降法技术,选用同成分化学计量的铌酸锂为初始原料,在合适的生长速度(1~4mm/h)与温度梯度(20~30℃/cm)下成功地生长出了无宏观缺陷、掺杂不同Cr3+离子浓度的铌酸锂单晶。测定了晶体的吸收光谱。Cr3+ 离子在晶体中以三价态存在,...用坩埚下降法技术,选用同成分化学计量的铌酸锂为初始原料,在合适的生长速度(1~4mm/h)与温度梯度(20~30℃/cm)下成功地生长出了无宏观缺陷、掺杂不同Cr3+离子浓度的铌酸锂单晶。测定了晶体的吸收光谱。Cr3+ 离子在晶体中以三价态存在,沿着生长方向晶体中 Cr3+ 离子的含量逐步减少。用顺磁共振谱(EPR)研究了晶体中 Cr3+离子的格位情况,结果表明Cr3+离子取代 Li 与 Nb 两种格位。测定了晶体的发射光谱并研究了发射强度随吸收强度的变化关系。展开更多
The quality of substrate crystals is critical to the performance of devices used in electronic and optoelectronic applications.These bulk crystals are mostly grown from the melt or solution,with a well controlled soli...The quality of substrate crystals is critical to the performance of devices used in electronic and optoelectronic applications.These bulk crystals are mostly grown from the melt or solution,with a well controlled solidification or supersaturation,which is affected significantly by the heat and mass flows.Particularly,in the melt growth,the interface kinetics is so fast that the growth is mainly controlled by the transport processes.Hence,the intricate coupling of heat and mass transfer and melt flow strongly influences the grown crystal quality,but its analysis and control is not a trivial task.For most materials,such as semiconductors and oxides,a detailed analysis of the transport processes through experiments is extremely difficult due to the long growth period at high temperature.Therefore,numerical simulation is inevitable.For the past ten years,crystal growth modeling has become one of the most active research fields in materials processing.Indeed,as long as the melt crystal growth of semiconductors remains a mainstay of the microelectronics industry,its modeling continues to be important.In this talk,the role of transport phenomena in bulk crystal growth and their detailed nonlinear analysis are illustrated through our research work over the years.Particular interests will be paid to the zone melting and Bridgman crystal growth.The control of convection and interface shape through external forces,such as rotation,magnetic fields,and vibration will be discussed.Interface instability leading to“pit formation”and interface breakdown due to thermal and solutal flows will also be illustrated.展开更多
文摘用坩埚下降法技术,选用同成分化学计量的铌酸锂为初始原料,在合适的生长速度(1~4mm/h)与温度梯度(20~30℃/cm)下成功地生长出了无宏观缺陷、掺杂不同Cr3+离子浓度的铌酸锂单晶。测定了晶体的吸收光谱。Cr3+ 离子在晶体中以三价态存在,沿着生长方向晶体中 Cr3+ 离子的含量逐步减少。用顺磁共振谱(EPR)研究了晶体中 Cr3+离子的格位情况,结果表明Cr3+离子取代 Li 与 Nb 两种格位。测定了晶体的发射光谱并研究了发射强度随吸收强度的变化关系。
文摘The quality of substrate crystals is critical to the performance of devices used in electronic and optoelectronic applications.These bulk crystals are mostly grown from the melt or solution,with a well controlled solidification or supersaturation,which is affected significantly by the heat and mass flows.Particularly,in the melt growth,the interface kinetics is so fast that the growth is mainly controlled by the transport processes.Hence,the intricate coupling of heat and mass transfer and melt flow strongly influences the grown crystal quality,but its analysis and control is not a trivial task.For most materials,such as semiconductors and oxides,a detailed analysis of the transport processes through experiments is extremely difficult due to the long growth period at high temperature.Therefore,numerical simulation is inevitable.For the past ten years,crystal growth modeling has become one of the most active research fields in materials processing.Indeed,as long as the melt crystal growth of semiconductors remains a mainstay of the microelectronics industry,its modeling continues to be important.In this talk,the role of transport phenomena in bulk crystal growth and their detailed nonlinear analysis are illustrated through our research work over the years.Particular interests will be paid to the zone melting and Bridgman crystal growth.The control of convection and interface shape through external forces,such as rotation,magnetic fields,and vibration will be discussed.Interface instability leading to“pit formation”and interface breakdown due to thermal and solutal flows will also be illustrated.
