Method for manufacturing a semiconductor device

Abstract

Provided are an etching method which uses an additive gas stably suppliable also in future, is reduced in the problem of particle contamination, is free from the problem of removability of side-wall protection film and has high shape controlling capacity, and a manufacturing method a highly-reliable semiconductor device by using this etching method. This etching method comprises depositing metal film including an aluminum over a semiconductor device and etching the metal film with a plasma of a mixture gas containing a Cl 2 gas, a BCl 3 gas and a CH 2 Cl 2 gas.

What is claimed is:  
     
         1 . A manufacturing method of a semiconductor device, which comprises depositing metal film including an aluminum over a semiconductor substrate, and etching the metal film with a plasma of a mixture gas containing a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas.  
     
     
         2 . A method of  claim 1 , wherein the pressure of the mixture gas is not greater than 1.5 Pa but 0.6 Pa or greater.  
     
     
         3 . A method of  claim 1 , wherein the CH 2 Cl 2  gas has a purity of 99.99% or greater.  
     
     
         4 . A method of  claim 1 , wherein the plasma is generated using an electromagnetic wave within a frequency range of 300 MHz to 1 GHz.  
     
     
         5 . A manufacturing method of a semiconductor device, which comprises forming a multilayer interconnection of metals including aluminum over a semiconductor substrate, wherein upon etching of the metal multilayer interconnection, a plasma of a mixture gas containing a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas is used.  
     
     
         6 . A method of  claim 5 , wherein the pressure of the mixture gas is not greater than 1.5 Pa but 0.6 Pa or greater.  
     
     
         7 . A method of  claim 5 , wherein the CH 2 Cl 2  gas has a purity of 99.99% or greater.  
     
     
         8 . A method of  claim 5 , wherein the plasma is generated using an electromagnetic wave within a frequency range of 300 MHz to 1 GHz.  
     
     
         9 . A manufacturing method of a semiconductor device, which comprises forming metal films by stacking a TiN film, an Al film and a TiN film successively over a semiconductor substrate, and etching the metal films with a plasma of a mixture gas of a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  additive gas, wherein the CH 2 Cl 2  gas is added in an amount of 0 to 4% upon etching of the TiN film, whereas the amount of the CH 2 Cl 2  gas is increased to 5 to 30% during etching of the Al film.  
     
     
         10 . A manufacturing method of a semiconductor device, which comprises depositing metal film including an aluminum over a semiconductor substrate, forming a resist mask over the metal film, etching the metal film with a plasma of a mixture gas of a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas, and removing the resist mask with a plasma of a mixture gas containing an F element and an O element.  
     
     
         11 . A manufacturing method of a semiconductor device, which comprises depositing metal film including an aluminum over a semiconductor substrate, forming patterns at a wiring pitch less than 500 nm over the metal film, and etching the metal film with a plasma of a mixture gas containing a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas.  
     
     
         12 . A manufacturing method of a semiconductor device, which comprises depositing metal film including an aluminum over a semiconductor substrate, forming, over the metal film, first mask patterns at a first wiring pitch and second mask patterns at a second wiring pitch wider than the first wiring pitch, and etching the metal films with a plasma of a mixture gas containing a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas.  
     
     
         13 . A manufacturing method of a semiconductor device, which comprises depositing metal film including an aluminum over a semiconductor substrate, forming, over the metal film, first patterns at a first wiring pitch and second patterns at a second wiring pitch wider than the first wiring pitch, and etching the metal film with a plasma of a mixture gas containing a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas.  
     
     
         14 . A manufacturing method of a semiconductor device, which comprises forming metal films over a semiconductor substrate by stacking a TiN film, an Al film and a TiN film one after another, and etching the metal films with a plasma of a mixture gas containing a Cl 2  gas, a BCl 3  gas and an additive gas obtained by diluting a CH 2 Cl 2  gas with a dilution gas, wherein the mole concentration of the CH 2 Cl 2  gas after dilution with the dilution gas is 10% to 100%.  
     
     
         15 . A manufacturing method of a semiconductor device, which comprises depositing metal film including an aluminum over a semiconductor substrate, and etching the metal film with a plasma formed, in a plasma etching system for generating a plasma by using an UHF-range electromagnetic wave, from a mixture gas containing a Cl 2  gas, a BCl 3  gas and a CH 2 Cl 2  gas.