Indium oxide conductive film structures
View Patent ↗One-transistor ferroelectric memory devices using an indium oxide film (In 2 O 3 ), an In 2 O 3 film structure, and corresponding fabrication methods have been provided. The method for controlling resistivity in an In 2 O 3 film comprises: depositing an In film using a PVD process, typically with a power in the range of 200 to 300 watts; forming a film including In overlying a substrate material; simultaneously (with the formation of the In-including film) heating the substrate material, typically the substrate is heated to a temperature in the range of 20 to 200 degrees C.; following the formation of the In-including film, post-annealing, typically in an O2 atmosphere; and, in response to the post-annealing: forming an In 2 O 3 film; and, controlling the resistivity in the In 2 O 3 film. For example, the resistivity can be controlled in the range of 260 to 800 ohm-cm.
1. A one-transistor ( 1 T) memory device using an indium oxide (In 2 O 3 ) film as a gate insulator, the device comprising:
a CMOS transistor gate, source, drain, and channel regions;
a gate insulator formed from an In 2 O 3 thin film, interposed between the channel region and the gate, having a resistivity in the range of 260 to 800 ohm-cm;
a memory cell film overlying the gate electrode; and,
a top electrode overlying the memory cell film.
2. The device of claim 1 wherein the In 2 O 3 thin film includes crystals having a grain size in the range of 3 to 30 nanometers (nm).
3. The device of claim 1 wherein the In 2 O 3 thin film has a thickness in the range 5 to 100 nm.
4. The device of claim 1 further comprising:
a material, interposed between the channel and the In 2 O 3 film, selected from the group including platinum (Pt), iridium (If), other noble Aetals, silicon (Si), high-k oxides, and silicon dioxide (SiO 2 ).
5. The device of claim 1 wherein the gate has a gate channel length of 0.1 micron; and,
wherein the In 2 O 3 film gate insulator has a resistivity of 700 ohm-cm.
6. The device of claim 1 wherein the gate has a gate channel length of 100 microns; and,
wherein the In 2 O 3 film gate insulator has a resistivity of 300 ohm-cm.
7. The device of claim 1 wherein the gate has a gate channel length in the range of 1 to 10 microns; and, wherein the In 2 O 3 film gate insulator has a resistivity in the range of 400 to 300 ohm-cm.
8. A one-transistor ( 1 T) memory device using an indium oxide (In 2 O 3 ) film as an insulator, the device comprising:
a CMOS transistor gate, source, drain, and channel regions;
an insulator formed from an In 2 O 3 thin film overlying the gate, having a resistivity in the range of 260 to 800 ohm-cm;
a memory cell film overlying the In 2 O 3 thin film; and,
a top electrode overlying the memory cell film.
9. The device of claim 8 wherein the 1 n 2 O 3 thin film includes crystals having a grain size in the range of 3 to 30 nanometers (nm).
10. The device of claim 8 wherein the In 2 O 3 thin film has a thickness in the range 5 to 100 nm.
11. The device of claim 8 further comprising:
a material, interposed between the memory cell film and the In 2 O 3 film, selected from the group including platinum (Pt), iridium (Ir), other noble metals, silicon (Si), high-k oxides, and silicon dioxide (SiO 2 ).
12. The device of claim 8 wherein the gate has a gate channel length of 0.1 micron; and,
wherein the In 2 O 3 film has a resistivity of 700 ohm-cm.
13. The device of claim 8 wherein the gate has a gate channel length of 100 microns; and,
wherein the In 2 O 3 film has a resistivity of 300 ohm-cm.
14. The device of claim 8 wherein the gate has a gate channel length in the range of 1 to 10 microns; and,
wherein the In 2 O 3 film has a resistivity in the range of 400 to 300 ohm-cm.
15. An indium oxide (In 2 O 3 ) film structure comprising:
a substrate; and,
an In 2 O 3 film overlying the substrate having a resistivity in the range of 260 to 800 ohm-cm.
16. The In 2 O 3 film structure of claim 15 wherein the substrate is selected from the group including platinum (Pt), iridium (Ir), other noble metals, silicon (Si), high-k oxides, and silicon dioxide (SiO 2 ).