Preparation And Performance Studies Of Ultra Low-k Organosiloxane Films

As size of IC devices shrink to 10 nm or less,the preparation and performance of integrated circuit interconnect materials has become a limitation affecting their development.New interconnect solutions that include ultra-low-k dielectric(ULK)materials and new integrated methods have became the first choice.The main obstacles of low-k material integration are lower mechanical and thermal properties.porous organosilicate glass(p-OSG)has become one of the most successful candidates,because of the strength and stiffness of p-OSG are realated to internal molecular structure and network connectivity.Based on this background,this project is dedicated to research to improve the mechanical properties of ultra-low k(k?2.2)dielectrics.The main results of the paper are as follows:1.Two types of porous SiOCH films having terminal and bridged alkyl groups were successfully prepared by sol-gel technique and spin coating process.The SiOCH film prepared in this experiment has the same chemical composition and porosity as the PECVD film reported in the literature,but the mechanical properties of all low-k films are better than those in the literature,and the concentration of bridging bonds in the SiOCH film increases,the modulus is also increases.YM of all films is above 4GPa(mechanical performance requirements for low k materials).TheSiOCH film having a bridged alkyl group between Si atoms is more likely to form a non-uniform internal pore structure(ink-bottle pore),and SiOCH film having a terminal alkyl group forms a cylindrical pore.2.The effects of different Brij30 concentrations.BTMSE/MTMS ratio,and annealing environment on alkyl-bridged SiOCH films were carefully evaluated and optimized.When the Brij30 content is between 30%and 50%and the BTMSE content is 47%(BTMSE content can be further improved),the pore radius is about 1.2-1.94 nm.the YM is up to 4 GPa.the water contact angle is greater than 90°,the film has the best overall performance.Thermal curing in an N2 environment effectively protects the Si-CH2-CH2-Si and Si-CH3 bonds from oxidation,retaining mechanical strength and hydrophobicity.3.In the extended application study of SiOCH film,Tb3+ was successfully incorporated into the sol and a luminescent film was prepared.The luminescent film has an optimum excitation wavelength of 225 nm and the highest emission peak intensity at 543 nm(5D4-7F5)When the mass ratio of doped Tb(NO3)3·6H2O to BTMSE-MTMS copolymer is 16%,the annealing condition is 150? for 60 minutes first,then the sample with 500? annealing for 10 minutes,these films have the best luminescence performance.The 543 nm emission peak area is 72%of the total emission area,Excellent monochromaticity,this film is a green luminescent film with excellent performance.