Research On Optimization For Detection Method Of Impurity Element In High Purity Trichlorosilane

Regardting high-purity trichlorosilane as the sample and taking boron,phosphorus and metallic impurity elements as research target,this thesis mainly searches pretreatment of sample and precisely measures relevant elements by using ICP-MS and disscuss measurement principle.Comparing factors of processing time,disturbance level,recovery rate,etc of wet digestion with Graphite fumigation,this thesis draws a conclusion that Graphite fumigation is the best digestion method of conducting trichlorosilane because it has following advantages: complete digestion,short-time process,high recovery rate,less matrix interference,simplicity of operator and high throughput capacity.To deal with the problem of volatility and lower recovery rate of element Boron in trichlorosilane,the research in this article of putting complex agents in and controling electric heating plate's temperature to raise the recovery rate of boron to90%.To sovle the problem of multi-interference of Phosphorus in trichlorosilane,the detection of using PO in stead of element P decrease the context of element P to30 CPS and decrease detection limition of element Phosphorus to 0.08ng/g.This thesis deeply discusses the usage of ICP-MS in trace analysis of metallic impurity elements in high-purity trichlorosilane,solves the problems of low equipment stability,low sensitivity,less measurement limitation and multi disturbance.It designs a series of methods to measure metallic impurity elements in high-purity trichlorosilane and makes following achievements: equipment stability RSD<3%,long-term stability RSD<5%,instrument detection limitation IDL<0.01ng/g,relevant coefficient of element curve R>0.9995.By optimizing equipment parament,it decrease the detection time of one sample from 2.0min to 1.5min,which shortens analysis time widely and solves bottleneck of quick destection of mass samples.It deelply analyzes the quality control factors in whole destecion,finds the reason of restrict analytical error in factors of people,instruments,matreial,methods and steps.It still provides a whole set of solutions and guarantees providing accurate data.