Molybdenum Sputtering Target Micro-electronics

In all application industries, micro-electronics semiconductor industry has high requirement to molybdenum sputtering target quality. Form now, 12 inches silicon wafer has been produce, but the interconnecting wire width is reducing. So silicon wafer manufacturers has more strict requirement to molybdenum sputtering target such as large size, high purity, low eliguation and fine grains the more strict required been asked the more great micro-structure molybdenum sputtering target is should be. And the target crystalline gain diameter and homogeneity was considered as critical factor for films deposition rate. On the other hand, films purity connect with target purity closely, in the past, 99.995%（4N5）copper target may meet semiconductor manufacturer 0.35pm technology demand but cannot meet 0.25um technology demand even 0.18um to 0.13um in the future. Because the purity require will up to 5 or 6N or more. Compare copper with aluminum, copper has high electromigration resistcance and low specific resistance which can meet conductor technology submicron wiring demand which under 0.25um but it also brought some problems. Because copper with other organic electric materials has low bind strength and easy react with this material so the copper wiring in the chip will corrosion and cause short circuit during using. In order to solve all these problems need to set a barrier layer between copper and dielectric layer. The material of dielectric layer is required high melting point, high resistivity metal and its compound, and the dielectric layer thickness should small than 50mm so it can has great adhesion property between cooper and dielectric material.

Copper-connection and aluminum-connection has different barrier material, so there need to develop new target material. The dielectric layer of copper-connection include Ta,W, TaSi , WSi and so on, but Ta and W belong to refractory metal and it is too difficult to produce so people will replace them by molybdenum or its alloy.