Semiconductor device, its manufacturing method, and sputtering target material for use in the method

Abstract

A semiconductor device enables a barrier layer to fully acquire a barriering property against the diffusion of Cu from a wiring main body and the diffusion of Si from an insulating film, enhances the adhesiveness of the barrier layer and the insulating film and excels in reliability of operation over a long period of time. In this invention, a semiconductor device provided on an insulating film with a wiring includes the insulating film containing silicon (Si), a wiring main body formed of copper (Cu) in a groove-like opening disposed in the insulating film, and a barrier layer formed between the wiring main body and the insulating film and made of an oxide containing Cu and Si and Mn.

1 . A sputtering target material adapted to form a copper alloy film by performing sputtering, comprising:
 copper (Cu);   manganese (Mn); and
 unavoidable impurities inevitably remaining in the copper (Cu) excluding the manganese (Mn), 
 wherein the unavoidable impurities are selected from one of eight groups with total atomic concentration of the selected group not more than 0.1% of the total target material, a first group consisting of lithium (Li), a second group consisting of beryllium (Be), calcium (Ca) and magnesium (Mg), a third group consisting of boron (B), gallium (Ga) and aluminum (Al), a fourth group consisting of silicon (Si), a fifth group consisting of antimony (Sb), a sixth group consisting of principal transition metals including scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), technetium (Tc), ruthenium (Ru), palladium (Pd), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt) and gold (Au), a seventh group consisting of inner transition metals of lanthanide series including lanthanum (La), cesium (Ce), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu) and an eighth group consisting of thorium (Th). 
   
   
   
       2 . A sputtering target material adapted to form a copper alloy film by performing sputtering, comprising:
 copper (Cu);   manganese (Mn); and
 unavoidable impurities inevitably remaining in the copper (Cu) excluding the manganese (Mn), 
 wherein the unavoidable impurities are selected from a group with total atomic concentration not more than 0.1% of the total target material, the group consisting of lithium (Li), beryllium (Be), calcium (Ca), magnesium (Mg), boron (B), gallium (Ga), aluminum (Al), silicon (Si), antimony (Sb), scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), technetium (Tc), ruthenium (Ru), palladium (Pd), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt) and gold (Au), lanthanum (La), cesium (Ce), samarium (Sm), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu) and thorium (Th). 
   
   
   
       3 . A sputtering target material adapted to form a copper alloy film by performing sputtering, comprising:
 copper (Cu);   manganese (Mn); and
 unavoidable impurities inevitably remaining in the copper (Cu) excluding the manganese (Mn), 
 wherein the unavoidable impurities are selected from one of seven groups with total atomic concentration of the selected group not more than 0.1% of the total target material, a first group consisting of lithium (Li), a second group consisting of beryllium (Be), calcium (Ca) and magnesium (Mg), a third group consisting of boron (B), gallium (Ga) and aluminum (Al), a fourth group consisting of silicon (Si), a fifth group consisting of antimony (Sb), a sixth group consisting of principal transition metals including, titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), palladium (Pd), tungsten (W), platinum (Pt) and gold (Au) and a seventh group consisting of thorium (Th). 
   
   
   
       4 . A sputtering target material adapted to form a copper alloy film by performing sputtering, comprising:
 copper (Cu);   manganese (Mn); and
 unavoidable impurities inevitably remaining in the copper (Cu) excluding the manganese (Mn), 
 wherein the unavoidable impurities are selected from a group with total atomic concentration not more than 0.1% of the total target material, the group consisting of lithium (Li), beryllium (Be), calcium (Ca), magnesium (Mg), boron (B), gallium (Ga), aluminum (Al), silicon (Si), antimony (Sb), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), palladium (Pd), tungsten (W), platinum (Pt), gold (Au) and thorium (Th). 
   
   
   
       5 . The sputtering target material of  claim 1 , wherein the sputtering target material has atomic concentration of the manganese (Mn) not less than 0.5% and not more than 20% of the total target material. 
   
   
       6 . The sputtering target material of  claim 1 , wherein the sputtering target material further includes at least one of elements consisting of zinc (Zn), germanium (Ge), strontium (Sr), silver (Ag), cadmium (Cd), indium (In), tin (Sn), barium (Ba), praseodymium (Pr) and neodymium (Nd). 
   
   
       7 . The sputtering target material of  claim 1 , wherein the sputtering target material is obtained by forming a copper (Cu) alloy in a plate shape, the copper alloy resulting from adding manganese (Mn) of purity exceeding 99.999% (5N) to copper (Cu) of purity exceeding 99.9999% (6N). 
   
   
       8 . The sputtering target material of  claim 5 , wherein the manganese (Mn) is obtained by a chelate resin ion-exchange method and purified until a total content of metallic impurities reaches not more than 200 ppm and a total content of nonmetallic impurities reaches not more than 10 ppm. 
   
   
       9 . The sputtering target material of  claim 5 , wherein the manganese (Mn) is obtained by electric field processing and purified until a total content of metallic impurities reaches not more than 200 ppm and a total content of nonmetallic impurities reaches not more than 10 ppm. 
   
   
       10 . The sputtering target material of  claim 5 , wherein the manganese (Mn) is obtained by a vacuum method for sublimation refining and purified until a total content of metallic impurities reaches not more than 200 ppm and a total content of nonmetallic impurities reaches not more than 10 ppm. 
   
   
       11 . The sputtering target material of  claim 1 , wherein the sputtering target material has a possibility to be utilized as a vacuum deposition source. 
   
   
       12 . The sputtering target material of  claim 1 , wherein the sputtering target material has a possibility to be utilized as a target material for a laser ablation method. 
   
   
       13 . The sputtering target material of  claim 1 , wherein the sputtering target material has a possibility to be utilized as a target material for a ion plating method. 
   
   
       14 . The sputtering target material of  claim 1 , wherein the sputtering target material has a possibility to be utilized as a target material for a ion cluster beam method. 
   
   
       15 . The sputtering target material of  claim 1 , wherein the sputtering target material has a possibility to be utilized as a target material for a plasma reaction method. 
   
   
       16 . The sputtering target material of  claim 1 , wherein the sputtering target material is utilized for a manufacturing method for a semiconductor device having an interconnection on an insulating film. 
   
   
       17 . The sputtering target material of  claim 16 , wherein the manufacturing method for the semiconductor device comprising the steps of:
 forming a groove on the insulating film including silicon (Si);   forming a copper alloy film on an inner surface of the groove by sputtering the sputtering target, the copper alloy film including manganese (Mn) and copper (Cu);   burying copper (Cu) in the groove so as to form a buried copper film; and   applying a heat treatment so as to form a barrier layer between the copper alloy film and the insulating film, and so as to form the interconnection by unifying the copper alloy film with the copper (Cu) in the buried copper film;   wherein the barrier layer including manganese (Mn)-based oxide having atomic concentration of manganese (Mn) maximized in a central part of a thickness of the barrier layer.   
   
   
       18 . The sputtering target material of  claim 16 , wherein the manufacturing method for the semiconductor device comprising the steps of:
 forming a groove on the insulating film including silicon (Si);   forming a copper alloy film on an inner surface of the groove by sputtering the sputtering target, the copper alloy film including manganese (Mn) and copper (Cu);   burying copper (Cu) in the groove so as to form a buried copper film; and   applying a heat treatment so as to form a barrier layer between the copper alloy film and the insulating film, and so as to form the interconnection by unifying the copper alloy film with the copper (Cu) in the buried copper film;   wherein the barrier layer is formed by an oxide including copper (Cu), silicon (Si) and manganese (Mn), the barrier layer having atomic concentration of copper (Cu) decreasing from the interconnection side toward the insulating film side, atomic concentration of silicon (Si) decreasing from the insulating film side toward the interconnection side and atomic concentration of manganese (Mn) being maximized in a region in which the atomic concentration of copper (Cu) and the atomic concentration of silicon (Si) are substantially the same.   
   
   
       19 . The sputtering target material of  claim 16 , wherein the manufacturing method for the semiconductor device comprising the steps of:
 forming a groove on the insulating film including silicon (Si);   forming a copper alloy film on an inner surface of the groove by sputtering the sputtering target, the copper alloy film including manganese (Mn) and copper (Cu);   applying a heat treatment so as to form a barrier layer between the copper alloy film and the insulating film; and   burying copper (Cu) in the groove so as to form the interconnection including copper (Cu);   wherein the barrier layer includes manganese (Mn)-based oxide having atomic concentration of manganese (Mn) maximized in a central part of a thickness of the barrier layer.   
   
   
       20 . The sputtering target material of  claim 16 , wherein the manufacturing method for the semiconductor device comprising the steps of:
 forming a groove on the insulating film including silicon (Si);   forming a copper alloy film on an inner surface of the groove by sputtering the sputtering target, the copper alloy film including manganese (Mn) and copper (Cu);   applying a heat treatment so as to form a barrier layer between the copper alloy film and the insulating film; and   burying copper (Cu) in the groove so as to form the interconnection including copper (Cu);   wherein the barrier layer is formed by an oxide including copper (Cu), silicon (Si) and manganese (Mn), the barrier layer having atomic concentration of copper (Cu) decreasing from the interconnection side toward the insulating film side, atomic concentration of silicon (Si) decreasing from the insulating film side toward the interconnection side and atomic concentration of manganese (Mn) being maximized in a region in which the atomic concentration of copper (Cu) and the atomic concentration of silicon (Si) are substantially the same.