Study On The Fabrication Technology Of Silicon-through-via In 3D Integrated System

3D integration technology is widely regarded as one of the main directions to continue Moore's law.Silicon through hole is one of the key points in 3d integration technology,which forms vertical electrical connection structure through etching,film growth,electroplating and other processes,and has the advantages of shortening the interconnect length,reducing signal delay and reducing power consumption.At present,the silicon through-hole is mainly developed in the direction of small size and high reliability.In this paper,the preparation process of silicon through hole is studied.The preparation process includes through hole etching,insulation layer growth,barrier layer preparation and conductive material filling.Specific work includes the following:A vertical through hole with a diameter of 13 m and a depth of 78 m was prepared by dry etching experiment.Based on dry etched through hole,the scallop grain was cut by circulating heat oxidation to improve the reliability of through hole.The thermal oxygen method was used to grow a layer of silica insulation layer with a thickness of about 700 nm.Based on the magnetron sputtering method,a layer of titanium film with a thickness of about 100 nm was sputtered on the side wall and the bottom of the hole as a potential barrier layer to achieve a good blocking effect and prevent copper from diffusing into the silicon substrate.Based on CAD software,the electroplating simulation model was established to simulate the filling of hole-free silicon through hole with diameter of 10 m and depth of 80 m.Finally,according to the size parameters of the silicon through hole,the reliability model is established,the thermal stress and electrical characteristics of the silicon through hole are simulated,and the influence of scallop grain on the reliability is studied.In this paper,through theoretical analysis,modeling,experimental verificationand reliability simulation verification,a complete si through hole is prepared and its reliability model is established,and the overall preparation process of si through hole and the influence of preparation process on reliability are studied.At the same time,the advantages and disadvantages of different technological experiments are analyzed.