Hafnium alloy target and process for producing the same
View Patent ↗A hafnium alloy target containing either or both of Zr and Ti in a gross amount of 100 wtppm-10 wt % in Hf, wherein the average crystal grain size is 1-100 μm, the impurities of Fe, Cr and Ni are respectively 1 wtppm or less, and the habit plane ratio of the plane {002} and three planes {103}, {014} and {015} lying within 35° from {002} is 55% or greater, and the variation in the total sum of the intensity ratios of these four planes depending on locations is 20% or less. As a result, obtained is a hafnium alloy target having favorable deposition property and deposition speed, which generates few particles, and which is suitable for forming a high dielectric gate insulation film such as HfO or HfON film, and the manufacturing method thereof.
1. A method of manufacturing a hafnium alloy target, comprising the steps of hot forging and rolling an ingot or billet of hafnium alloy and thereafter heating said ingot or billet to 800-1300° C. for at least 15 minutes in an atmosphere, a vacuum, or an inert gas atmosphere, said rolling step is hot rolling or cold rolling, and said target is produced such that said target contains at least one of Zr and Ti in a gross amount of 100 wtppm-10 wt % in Hf and has a habit plane ratio of a plane {002} and of three planes {103}, {014} and {015} lying within 35° from {002} of at least 55%, a variation in a total sum of intensity ratios of these four planes depending on locations of 20% or less, an average crystal grain size of 1-100 μm, impurities of Fe, Cr and Ni of 1 wtppm or less, respectively, and an average roughness Ra of an erosion face of said target of 0.01-2 μm.
2. A method according to claim 1 , further comprising the step of diffusion bonding the hafnium alloy target to a backing plate.
3. A method according to claim 2 , wherein the backing plate is made of the material selected from the group consisting of Al, an Al alloy, Cu, the Cu alloy, Ti and the Ti alloy.
4. A method according to claim 3 , further comprising the step of bead blasting, etching or metal spraying a non-erosion face of the target to provide the non-erosion face with an average roughness Ra of 2-50 μm.
5. A method according to claim 1 , further comprising the step of bead blasting, etching or metal spraying a non-erosion face of the target to provide the non-erosion face with an average roughness Ra of 2-50 μm.