随着集成电路向高密度小尺寸方向发展,铜互连已成为目前集成电路主要使用的互连技术,但球状缺陷的形成会影响产品的质量.本文研究了长等待时间下铜互连线中球状缺陷的形成机理,分析了其造成器件失效的原因,并提出了相应的解决方案.研究显示,前道工序应力残留致铜晶界处应变再结晶是这种形式球状缺陷形成的主要原因.球状缺陷会使两层金属之间形成额外通孔,从而引起短路或漏电,导致器件失效.最后提出了相应的解决方案,通过正交实验发现铜电镀退火温度降低50℃,氮化硅淀积速率降低1 nm/s,氮化硅的膜厚提高10 nm能够有效改善这一现象.

Dynamic random access memory(DRAM)suffers from the bridge issue due to the WSix residue on gate sidewall,which is the bottleneck to enhancing the product's yield and reliability.Thus,the Si/W atomic ratio of WSix is optimized to 2.45 by using X-ray fluorescence(XRF)and scanning electron microscope(SEM).Analysis by transmission electron microscopy(TEM)and electronic testing shows that after 30 s rapid thermal annealing(RTA)at 1 000 ℃,the sheet resistance of WSi2.45 film is 12 Ω/cm2 and can be easily etched off.Electron beam scanning before the WSix film etching shows that about 84.7% of the surface particles and polymer residue can be effectively removed through a novel wet cleaning process by 15 min HF and 10 min sulfuric-peroxide mixture(SPM)with 300 W megasonic.With these integrated optimized processes,the yield loss due to the WSix residue on the 65 nm DRAM products can be reduced from the original 31.3% to 1.9%,which also serves as a good guideline for future advanced DRAM process development.

When Boron and Phosphorous had been alternately implanted with the same implanter,the PF molecules would be generated,due to the P+ residue reacted with F cracked from BF3.It is pointed out that the average mass of dopant into the wafer following normal distribution,with the target dopant mass as center value.The potential overlap area between the distributions of 49BF2+ and 50PF+ was the root cause of phosphorus contamination.In order to prevent PF contamination real time,the precision of mass analyzer had been improved.When the beam current is increased to be 800 μA,It is found that the implanter couldn't detect PF with mass analyzer's AMU setting at 49±0.5.After 80 h P+ and alternately specie implanted,worse experiments had been studied on the implanter.When the arc current is 3 100 μA,the result of sheet resistance indicates that no PF found by setting AMU at 49±0.3(m/Δm=169.3).Four parameters of worse conditions had been combined together to test the solution's reliability as following: worse implanter,higher arc current at 3 100 μA,higher beam current at 800 μA and higher 49BF2+ dosage at 2.2×1015.Even with the combined worse conditions,the analysis result of SIMS showed that no Phosphorus peak found for two samples by setting AMU at 49±0.3.This solution is proved to be effective during the mass production by controlled the AMU setting value of improved mass analyzer,so it is not necessary to the keep the original high cost solution by Frederic Sahores(2002 IEEE),such as increasing the frequence of cleaning or dedicated one implanter to one dopant.

This paper describes the importance of applying the properties of ceramic coatings by plasma spraying,which can efficiently solve the invalid mechanical parts.This paper indicates six different types of wear on the surface of metal material,and analyzes the resistance to wear of the surface by quoting the practical data from experiments and productions.It proves that the resistane to wear of the surface have been improved greatly after plasma spraying ceramic material.After spraying the ceramic material which can resist the corruptible matter from the metal body,the resistance to corrosion can be improved.And the data of experiments proves that the resistance to corrosion can be improved greatly by obturating or laser rewelting,which can reduce the rate of pores.This paper also studies the good properties of ceramic coatings which are fit for high temperature,and enumerates three typical kinds of ceramic coatings which are fit for high temperature condition.In the last,this paper indicates the trend of development and some problems which shall be urgent to be solved now.