Semiconductor device and method for manufacturing the same

Abstract

In a semiconductor device including a transistor including a gate electrode formed over a substrate, a gate insulating film covering the gate electrode, a multilayer film overlapping with the gate electrode with the gate insulating film provided therebetween, and a pair of electrodes in contact with the multilayer film, a first oxide insulating film covering the transistor, and a second oxide insulating film formed over the first oxide insulating film, the multilayer film includes an oxide semiconductor film and an oxide film containing In or Ga, the oxide semiconductor film has an amorphous structure or a microcrystalline structure, the first oxide insulating film is an oxide insulating film through which oxygen is permeated, and the second oxide insulating film is an oxide insulating film containing more oxygen than that in the stoichiometric composition.

1 . (canceled) 
     
     
         2 . A semiconductor device comprising:
 a gate electrode over a substrate, the gate electrode including a first conductive layer and a second conductive layer over the first conductive layer;   a gate insulating film over the gate electrode;   an oxide semiconductor film over the gate insulating film, the oxide semiconductor film including indium, gallium and zinc;   an oxide film over the oxide semiconductor film, the oxide film including indium, gallium and zinc;   a pair of electrodes in electrical contact with the oxide film;   an oxide insulating film over the oxide film and the pair of electrodes, the oxide insulating film including silicon; and   a nitride insulating film over the oxide insulating film, the nitride insulating film including silicon,   wherein the first conductive layer includes at least one selected from the group consisting of aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten,   wherein the second conductive layer includes at least one selected from the group consisting of aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten,   wherein a thickness of the oxide insulating film is larger than a thickness of the nitride insulating film, and   wherein an atomic ratio of gallium to indium in the oxide film is higher than an atomic ratio of gallium to indium in the oxide semiconductor film.   
     
     
         3 . The semiconductor device according to  claim 2 , wherein the oxide insulating film contains more oxygen than a stoichiometric composition. 
     
     
         4 . A display module comprising the semiconductor device according to  claim 2 . 
     
     
         5 . An electronic device comprising the semiconductor device according to  claim 2 . 
     
     
         6 . A semiconductor device comprising:
 a gate electrode over a substrate, the gate electrode including a first conductive layer and a second conductive layer over the first conductive layer;   a gate insulating film over the gate electrode;   an oxide semiconductor film over the gate insulating film, the oxide semiconductor film including indium, gallium and zinc;   an oxide film over the oxide semiconductor film, the oxide film including indium, gallium and zinc;   a pair of electrodes in electrical contact with the oxide film;   an oxide insulating film over the oxide film and the pair of electrodes, the oxide insulating film including silicon; and   a nitride insulating film over the oxide insulating film, the nitride insulating film including silicon,   wherein the first conductive layer includes at least one selected from the group consisting of aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten,   wherein the second conductive layer includes at least one selected from the group consisting of aluminum, chromium, copper, tantalum, titanium, molybdenum, and tungsten,   wherein a thickness of the oxide insulating film is larger than a thickness of the nitride insulating film,   wherein an atomic ratio of gallium to indium in the oxide film is higher than an atomic ratio of gallium to indium in the oxide semiconductor film, and   wherein the oxide insulating film is in contact with a portion of the oxide film.   
     
     
         7 . The semiconductor device according to  claim 6 , wherein the oxide insulating film contains more oxygen than a stoichiometric composition. 
     
     
         8 . A display module comprising the semiconductor device according to  claim 6 . 
     
     
         9 . An electronic device comprising the semiconductor device according to  claim 6 .