Gettering of copper impurity in silicon by aluminum precipitates and cavities  

作　　者：WU Yan-Jun, ZHANG Miao, ZHANG Ning-Lin, LIN Cheng-Lu(State Key Laboratory of Functional Materials for Informatics. Shanghai Institute of Microsystem and Information Technology.the Chinese Academy of Sciences, Shanghai 200050) 

出　　处：《Nuclear Science and Techniques》2003年第3期164-167,共4页核技术（英文）

基　　金：Supported by the National Natural Science Foundation of China(No.69906005)and the Shanghai Youth Foundation(No.01QMH1403)

摘　　要：Al precipitates as well as cavities (or open-volume detects) are known for their ability to getter impuri-ties within Si. In order to compare their relative gettering strength we produced both Al precipitates and cavities atdifferent depths within one Si wafer. This was done by H+ and Al+ implantation with different energies and subse-quent annealing process, resulting in Al-Si alloy and cavities at depth of 300 nm and 800 nm, respectively. Cu wasthen implanted with an energy of 70 keV to a fluence of 1 × 1014 / cm2. The Cu implanted samples were annealed attemperature from 700℃ to 1200℃. It was found that Cu impurities were gettered primarily by the precipitated Allayer rather than by cavities at the temperature of 700～1000℃, while gettering of Cu occured in both regions at thetemperature of 1200℃. The secondary ion mass spectrometry and transmission electron microscopy analyses wereused to reveal the interaction between Cu impurities and defects at different trap sites.Al precipitates as well as cavities (or open-volume defects) are known for their ability to getter impurities within Si. In order to compare their relative gettering strength we produced both Al precipitates and cavities at different depths within one Si wafer. This was done by H+ and Al+ implantation with different energies and subsequent annealing process, resulting in Al-Si alloy and cavities at depth of 300 nm and 800 nm, respectively. Cu was then implanted with an energy of 70 keV to a fluence of 1 X 1014 / cm'. The Cu implanted samples were annealed at temperature from 700C to 1200C. It was found that Cu impurities were gettered primarily by the precipitated Al layer rather than by cavities at the temperature of 700~1000C, while gettering of Cu occured in both regions at the temperature of 1200C. The secondary ion mass spectrometry and transmission electron microscopy analyses were used to reveal the interaction between Cu impurities and defects at different trap sites.

关 键 词：铜 硅片 铝 过渡金属元素 

分 类 号：TN305.3[电子电信—物理电子学]