Patent ID: 7791072

Claim:
An active matrix display comprising: a light control device; and a field effect transistor for driving the light control device, wherein an active layer of the field effect transistor comprises an amorphous oxide of a compound having (a) a composition when in a crystalline state represented by In 2-x M3 x O 3 (Zn l-y M2 y O) m , wherein M2 is Mg or Ca; M3 is B, Al, Ga or Y; 0≦x≦2; 0≦y≦1; and m is zero or a natural number less than 6, or a mixture of said compounds; (b) an electron carrier concentration of 10 12 /cm 3 or more and less than 10 18 /cm 3 , wherein an electron mobility of the active layer tends to increase with increasing electron carrier concentration and wherein a current between drain and source terminals of the field effect transistor when no gate voltage is applied is less than 10 microamperes ; and (c) controlled oxygen defect density resulting from subjecting the amorphous oxide to treatment in an atmosphere containing oxygen at a predetermined pressure upon or after film formation thereof.