Method of manufacturing semiconductor device and semiconductor device

Abstract

A first region is formed by injecting a first condition type first dopant into a surface layer portion of an IGBT section of a semiconductor substrate. A second region is formed by injecting a second condition type second dopant into a region of the IGBT section shallower than the first region. An amorphous third region is formed by injecting the first conduction type third dopant into a surface layer portion of a diode section at a concentration higher than that of the second dopant. Thereafter, the IGBT section and the diode section are laser-annealed under conditions in which the third region is partially melted and the first dopant is activated. Subsequently, a surface layer portion which is shallower than the second injection region in the entire region of the IGBT section and the diode section is melted and crystallized by annealing the IGBT section and the diode section.

What is claimed is: 
     
         1 . A method of manufacturing a semiconductor device comprising:
 (a) a process of forming a first injection region by ion-injecting a first conduction type of first dopant into a surface layer portion of an IGBT section of a semiconductor substrate including a surface in which the IGBT section and a diode section are defined;   (b) a process of forming a second injection region by ion-injecting a second dopant of a second conduction type which is the opposite to the first conduction type into a shallower region of the IGBT section of the semiconductor substrate than the first injection region;   (c) a process of forming a third injection region by ion-injecting the first conduction type of third dopant into a surface layer portion of the diode section of the semiconductor substrate at a concentration higher than the concentration of the second dopant so that the injected region becomes amorphized;   (d) a process of scanning the IGBT section and the diode section of the semiconductor substrate with a first pulse laser beam under conditions in which the third injection region is partially melted and the first dopant of the first injection region is activated after the processes (a), (b), and (c); and   (e) a process of melting and crystallizing a surface layer portion which is shallower than the second injection region in the entire region of the IGBT section and the diode section of the semiconductor substrate by scanning the IGBT section and the diode section of the semiconductor substrate with a second pulse laser beam having a pulse width shorter than the pulse width of the first pulse laser beam after the process (d).   
     
     
         2 . The method of manufacturing a semiconductor device according to  claim 1 ,
 wherein the IGBT section and the diode section of the semiconductor substrate are scanned with the first pulse laser beam under conditions in which the IGBT section of the semiconductor device is not melted, in the process (d).   
     
     
         3 . The method of manufacturing a semiconductor device according to  claim 1 ,
 wherein the third injection region formed in the process (c) is shallower than the first injection region formed in the process (a).   
     
     
         4 . A method of manufacturing a semiconductor device comprising:
 (a) a process of forming a first injection region by ion-injecting a first conduction type of first dopant into a surface layer portion of an IGBT section of a semiconductor substrate including a surface in which the IGBT section and a diode section are defined;   (b) a process of activating the first dopant of the first injection region by scanning the IGBT section and the diode section of the semiconductor substrate with a first pulse laser beam under conditions in which the surface of the semiconductor substrate is not melted;   (c) a process of forming a second injection region by ion-injecting a second dopant of a second conduction type which is the opposite to the first conduction type into a shallower region of the IGBT section of the semiconductor substrate than the first injection region after the process (b);   (d) a process of forming a third injection region by ion-injecting the first conduction type of third dopant into a surface layer portion of the diode section of the semiconductor substrate at a concentration higher than the concentration of the second dopant so that the injected region becomes amorphized; and   (e) a process of scanning the IGBT section and the diode section of the semiconductor substrate with a second pulse laser beam having a pulse width shorter than the pulse width of the first pulse laser beam after the processes (c) and (d) and melting and crystallizing at least the surface layer portions of the second injection region and the third injection region of the semiconductor substrate to activate the second dopant and the third dopant.   
     
     
         5 . The method of manufacturing a semiconductor device according to  claim 4 ,
 wherein the semiconductor substrate is scanned with the first pulse laser beam used in the process (b) under conditions in which at least the surface layer portion of the amorphized third injection region formed in the process (d) is melted.   
     
     
         6 . A semiconductor device comprising:
 a first ion injection unit which forms a first injection region by ion-injecting a first conduction type of first dopant into a surface layer portion of an IGBT section of a semiconductor substrate including a surface in which the IGBT section and a diode section are defined;   a second ion injection unit which forms a second injection region by ion-injecting a second dopant of a second conduction type which is the opposite to the first conduction type into a shallower region of the IGBT section of the semiconductor substrate than the first injection region; and   a third ion injection unit which forms a third ion injection region by ion-injecting the first conduction type of third dopant into a surface layer portion of the diode section of the semiconductor substrate at a concentration higher than the concentration of the second dopant so that the injected region becomes amorphized,   wherein the IGBT section and the diode section of the semiconductor substrate are scanned with a first pulse laser beam under the conditions in which the third injection region is partially melted and the first dopant of the first injection region is activated, and   a surface layer portion which is shallower than the second injection region is melted and crystallized in the entire region of the IGBT section and the diode section of the semiconductor substrate by scanning the IGBT section and the diode section of the semiconductor substrate with a second pulse laser beam having a pulse width shorter than the pulse width of the first pulse laser beam after the scanning of the first pulse laser beam.   
     
     
         7 . The semiconductor device according to  claim 6 ,
 wherein the third injection region is shallower than the first injection region.   
     
     
         8 . A semiconductor device comprising:
 a first ion injection unit which forms a first injection region by ion-injecting a first conduction type of first dopant into a surface layer portion of an IGBT section of a semiconductor substrate including a surface in which the IGBT section and a diode section are defined;   a second ion injection unit which forms a second injection region by ion-injecting a second dopant of a second conduction type which is the opposite to the first conduction type into a shallower region of the IGBT section of the semiconductor substrate than the first injection region; and   a third ion injection unit which forms a third ion injection region by ion-injecting the first conduction type of third dopant into a surface layer portion of the diode section of the semiconductor substrate at a concentration higher than the concentration of the second dopant so that the injected region becomes amorphized,   wherein the first dopant of the first injection region is activated by scanning the IGBT section and the diode section of the semiconductor substrate with a first pulse laser beam under conditions in which the surface of the semiconductor substrate is not melted, and   the IGBT section and the diode section of the semiconductor substrate are scanned with a second pulse laser beam having a pulse width shorter than the pulse width of the first pulse laser beam and at least the surface layer portions of the second injection region and the third injection region of the semiconductor substrate are melted and crystallized to activate the second dopant and the third dopant.