An active matrix display comprising a light control device and a field effect transistor for driving the light control device. The active layer of the field effect transistor comprises an amorphous.
1. 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.
2. An active matrix display according to claim 1 , wherein the amorphous oxide additionally contains at least one of Sn and a Group IV element selected from Si, Ge or Zr.
3. An active matrix display according to claim 1 , wherein the amorphous oxide comprises an oxide containing In, Ga, and Zn.
4. An active matrix display according to claim 1 , wherein the light control device contains one of a liquid crystal and an electrophoretic particle.
5. An active matrix display according to claim 4 , wherein the insulation film comprises one of a silicon oxide film and a silicon nitride film.
6. An active matrix display according to claim 1 , wherein the light control device contains a liquid crystal, and has an orientation film and an insulation film arranged in this order from a side of the liquid crystal between the active layer and the liquid crystal.
7. An active matrix display according to claim 1 , wherein the light control device contains a liquid crystal, and has an orientation film and an insulation film arranged in this order from a side of the liquid crystal between a gate electrode of the field effect transistor and the liquid crystal.
8. An active matrix display according to claim 1 , wherein the light control device is arranged on a flexible resin substrate.
9. An active matrix display according to claim 1 , wherein the light control device is arranged on a light transmissive substrate.
10. An active matrix display comprising:
a first electrode;
a second electrode;
a liquid crystal interposed between the first and second electrodes; and
a field effect transistor for driving the liquid crystal,
wherein an active layer of the 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) a 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 a treatment in an atmosphere containing oxygen at a predetermined pressure upon or after film formation thereof.
11. An active matrix display according to claim 10 , wherein the amorphous oxide additionally contains at least one of Sn and a Group IV element selected from Si, Ge or Zr.
12. An active matrix display according to claim 11 , further comprising an orientation film and an insulation film arranged in this order from a side of the liquid crystal between a gate electrode of the field effect transistor and the liquid crystal.