| 摘要 |
<p>ELECTRICAL MULTILAYER CONTACT FOR MICROELECTRONIC STRUCTURE A guided interracial reaction is utilized which is to finish soon and to result in the formation of an equilibrium (or near equilibrium in actual practice) diffusion barrier. Illustratively, for a diffusion barrier between A (e.g., Al) and B (e.g., Si) the exemplary barrier layer in accordance with the principles of this invention is an alloy of MxNy (e.g., Pd20W80) satisfying the following criteria: (1) M is an element which reacts with both A and B to form compounds; and (2) N does not react with either A or B in compound formation in the presence of M. A low mutual solid solubility of M and N is desirable. Thus, N-A, and N-B eutectic systems are suitable for N and M. The composition of the alloy is preferably rich in N. The alloy can be made by codeposition or sputtering with the sandwich structure of A/MxNy/B being made in one pump-down without breaking vacuum. A thermal annealing is introduced to engage reactions between A and MxNy and between MXNy and B, thereby forming compounds AMi and BMj, respectively. Thermal annealing is introduced after all three layers are deposited to obtain a multilayer structure: =A1/AMi=A13Pd/N(M)=W(Pd)/BMj= Pd2 Si/B=Si. The extent of these reactions can be controlled by tailoring the concentration of M in the alloy. All M cannot be depleted from N(M) because of entropy of mixing and equilibrium will be reached when the compound formation energy equals the partial molar free energy of M in N.</p> |
