Summary

To summarize, there are two conclusions for Ti/TiN/SiO2/PtFe structure with different thermal treatment conditions.

(a) Small devices of Ti/TiN/SiO2/PtFe structure possess low power consumption properties.

(b) Electrical characteristics and parameters of small devices could understand more clearly the physical mechanism and current transport of resistance switching behaviors for Ti/TiN/SiO2/PtFe structure.

Table 3.1. Average current of as deposition, RTA and FA sample at HRS (LRS).

Average current As-deposit RTA FA

LRS (uA)

242.95 397.66 3.47*10

³

HRS (uA)

2.92 24.04 34.35

Pt (50 nm) SiO ₂ (500 nm)

P-Si (100) Al

Al SiO SiO _{2 2} (50nm) (50nm) Voltage Sweep

Pt (50 nm) SiO ₂ (500 nm)

P-Si (100) Al

Al SiO SiO _{2 2} (50nm) (50nm)

Pt (50 nm) SiO ₂ (500 nm)

P-Si (100) Al

Al SiO SiO _{2 2} (50nm) (50nm) Voltage Sweep

Figure 3.1. Schematic measurement setup diagram of Al/SiO2/PtFe/SiO2/Si structure.

Pt (50 nm)

SiO ₂ (500 nm) P-Si (100)

Al Al Al Al

Al

Al SiO SiO _{2 2} (50nm) (50nm)

Pt (50 nm)

SiO ₂ (500 nm) P-Si (100)

Al Al Al Al

Al

Al Al Al Al Al

Al

Al SiO SiO _{2 2} (50nm) (50nm)

Figure 3.2. Schematic diagram of Al/SiO2/Pt/SiO2/Si structure.

P P -type Si - type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

Pt (50nm)

400nm Al deposited by sputtering, then deposited by sputtering, then electrode patterning & etching (100*100um electrode patterning & etching (100*100um ^{2 2} ) )

P P -type Si - type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

Pt (50nm)

Wet oxidation (500nm) Wet oxidation (500nm)

Pt (50nm)

400nm Al deposited by sputtering, then deposited by sputtering, then electrode patterning & etching (100*100um electrode patterning & etching (100*100um ^{2 2} ) )

Figure 3.3. Process flows of Ti/TiN/SiO2/Pt/SiO2/Si structure.

SiO ₂

Top electrode

Bottom electrode

SiO ₂ (High Resistance State) Al top electrode (Ground)

Pt bottom electrode (-)

SiO ₂

Top electrode

Bottom electrode

SiO ₂ (High Resistance State) Al top electrode (Ground)

Pt bottom electrode (-)

Figure 3.4. Initial state of Al/SiO2/Pt/SiO2/Si structure.

3

Voltage (V)

-2 -1 0 1 2

Current (A)

10 ^-7 10 ^-6 10 ^-5 10 ^-4 10 ^-3 10 ^-2 10 ^-1

4

1

3

Area: 100*100 um

²

2

Figure 3.5. I-V characteristics of Al/SiO2/Pt structure after forming.

PtFe (50 nm) SiO ₂ (500 nm)

P-Si (100)

Al Al Al Al

Al

Al SiO SiO _{2 2} (50nm) (50nm)

PtFe (50 nm) SiO ₂ (500 nm)

P-Si (100)

Al Al Al Al

Al

Al Al Al Al Al

Al

Al SiO SiO _{2 2} (50nm) (50nm)

Figure 3.6. Schematic diagram of Al/SiO2/PtFe/SiO2/Si structure.

P- P -type Si type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

PtFe (50nm)

400nm Al deposited by sputtering, then deposited by sputtering, then electrode patterning & etching (100*100um electrode patterning & etching (100*100um

²²

) )

P- P -type Si type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

PtFe (50nm)

Wet oxidation (500nm) Wet oxidation (500nm)

PtFe (50nm)

400nm Al deposited by sputtering, then deposited by sputtering, then electrode patterning & etching (100*100um electrode patterning & etching (100*100um

²²

) )

Figure 3.7. Process flows of Ti/TiN/SiO2/PtFe/SiO2/Si structure.

Voltage (V)

Figure 3.8. I-V characteristics of Ti/TiN/SiO2/PtFe structure during set and reset processes.

Voltage (V)

Figure 3.9. I–V characteristics during the forming process in the Al/SiO2/Pt structure.

--Figure 3.10. Impact ionization breakdown in the Al/SiO2/Pt structure.

Bottom electrode Pt bottom electrode (-)

Top electrode

SiO ₂ (Low resistance paths) Al top electrode (+)

Bottom electrode Pt bottom electrode (-)

Top electrode

SiO ₂ (Low resistance paths) Al top electrode (+)

Figure 3.11. After forming process in Al/SiO2/Pt/SiO2/Si structure. There is some low resistance paths produced in SiO2 insulating film.

Fe ₂ O ₃ SiO ₂

Top electrode

Bottom electrode

Fe ₂ O ₃ (High Resistance Region) SiO ₂ (High Resistance State) Ti/TiN top electrode

PtFe bottom electrode Fe ₂ O ₃

SiO ₂

Top electrode

Bottom electrode Fe ₂ O ₃

SiO ₂

Top electrode

Bottom electrode

Fe ₂ O ₃ (High Resistance Region) SiO ₂ (High Resistance State) Ti/TiN top electrode

PtFe bottom electrode

Figure 3.12. Initial state of Al/SiO2/PtFe structure.

Voltage (V)

Figure 3.13. I–V characteristics during the forming process in the Al/SiO2/PtFe structure.

--Figure 3.14. Impact ionization breakdown in Al/SiO2/PtFe structure.

Bottom electrode

PtFe bottom electrode (+)

Top electrode

SiO ₂ (Low resistance paths) Al top electrode (-)

Fe ₂ O ₃ Fe ₃ O ₄ or Oxygen Vacancies

Figure 3.15. After forming process for Al/SiO2/PtFe structure, there is some low resistance paths produced in SiO2 and Fe2O3 insulating film.

Fe ₂ O ₃

PtFe Cathode (-)

O

2-O ^2- O 2-O 2-O

2-O

2-O 2-O

2-SiO ₂

E TiN Anode (+)

(a) 2 Fe ₃ O ₄ + O ^-- => 3 Fe ₂ O ₃ + 2 e

- 2-''

Bias

Forward V (donor) O

O

(b) ← ⎯ ⎯ ⎯ ⎯ ⎯ +

Figure 3.16. During reset process for Al/SiO2/PtFe structure, the oxygen ion would be attracted to the bottom electrode because of the electrical field.

Temperature (K)

400 600 800 1000 1200 1400 1600 1800

Gibbs free energy (kJ/mol)

-1.2x10

⁶

400 600 800 1000 1200 1400 1600 1800

Gibbs free energy (kJ/mol)

-1.2x10

⁶

Figure 3.17. During reset process for Al/SiO2/PtFe structure, the localization Joule heating up to 1000K would let Fe2O3 form.

Bottom electrode

PtFe bottom electrode (+)

Top electrode

SiO

₂

(Low resistance paths) Al top electrode (-)

Fe

₂

O

₃ ^{Fe3O4 + O2-}

Fe ₃ O ₄ => Fe ₂ O ₃

Bottom electrode

PtFe bottom electrode (+)

Top electrode

SiO

₂

(Low resistance paths) Al top electrode (-)

Fe

₂

O

₃ ^{Fe3O4 + O2-}

Fe ₃ O ₄ => Fe ₂ O ₃

Figure 3.18. After reset process for Al/SiO2/PtFe structure, the Fe3O4 would change phase to Fe2O3.

E _F

E ^v E ^c E _F Fe ₂ O ₃

Lighted n - type

(b)

: Oxygen vacancies ( donor type)

e ^- e ^- e ^- e

Lighted n - type

(b)

: Oxygen vacancies ( : Oxygen vacancies (

e ^- e ^- e ^- e

Lighted n - type

(b)

: Oxygen vacancies ( donor type)

e ^- e ^- e ^- e

Lighted n - type

(b)

: Oxygen vacancies ( : Oxygen vacancies (

e ^- e ^- e ^- e

-V

_F

Frenkel-Poole emission

＋ ＋ ＋

＋

Figure 3.19. Band diagram of high resistance state for lighted n-type Fe2O3

semiconductor.

1/T (K-1)

0.0026 0.0028 0.0030 0.0032

ln (J/V)

Figure 3.20. For Ti/TiN/SiO2/PtFe structure, current fitting of Frenkel-Poole emission in the high bias region at HRS (section 3.4.4).

(a) 2 Fe ₃ O ₄ + O ^-- ↑ ^{<= 3 Fe} ₂ ^O ₃ ^{+ 2 e}

Negative V (donor) O

O

Negative V (donor) O

O

Negative V (donor) O

O

(b) ⎯ ⎯ ⎯ ⎯ ⎯ → +

Figure 3.21. During set or forming process for Al/SiO2/PtFe structure, the oxygen ion would be repelled to the bottom electrode because of the electrical field.

Bottom electrode

PtFe bottom electrode (+)

Top electrode

SiO

₂

(Low resistance paths) Al top electrode (-)

Fe

₂

O

₃ ^{Fe3O4 + O2-}

Fe ₂ O ₃ => Fe ₃ O ₄

Bottom electrode

PtFe bottom electrode (+)

Top electrode

SiO

₂

(Low resistance paths) Al top electrode (-)

Fe

₂

O

₃ ^{Fe3O4 + O2-}

Fe ₂ O ₃ => Fe ₃ O ₄

Figure 3.22. After set or forming process for Al/SiO2/PtFe structure, the Fe2O3 would change phase to Fe3O4 at some electric faucet regions.

E ^v

Enhanced n - type

E ^c Fe ₂ O ₃

: Oxygen vacancies (donor type) : Oxygen vacancies (donor type) (a)

E _F

＋

E _F

＋

V

_R

e

-Tunneling

e

-＋

＋＋

＋

＋

＋ ＋＋ ＋＋ ＋＋

＋

＋＋

＋ ＋＋＋＋ ＋＋ ＋＋ ＋＋

e ^- e ^- e

-Figure 3.23. Band diagram of low resistance state for enhanced n-type Fe2O3

semiconductor.

Temperature (K)

280 300 320 340 360 380 400 420

Current (A)

0 10

^-3

2x10

^-3

3x10

^-3

4x10

^-3

5x10

^-3

Figure 3.24. For Ti/TiN/SiO2/PtFe structure, the relationship between tunneling current and different temperature at LRS (section 3.4.4).

Voltage (V)

Figure 3.25 (a). I-V curve of Al/SiO2/PtFe structure.

Voltage (V)

Figure 3.25 (b). I-V curve of Ti/TiN/SiO2/PtFe structure.

Voltage (V)

Figure 3.25 (c). I-V curve of W probe/SiO2/PtFe structure.

PtFe (50 nm)

Figure 3.26 (a). Schematic diagram of Ti/TiN/SiO2 (50nm)/PtFe structure.

PtFe (50 nm) SiO ₂ (500 nm)

P-Si (100) TiN TiN TiN TiN TiN TiN TiN TiN TiN TiN

TiN SiO SiO _{2 2} (30nm) (30nm)

Ti

Ti Ti Ti Ti Ti

Figure 3.26 (b). Schematic diagram of Ti/TiN/SiO2 (30nm)/PtFe structure.

Forming electrical field: 5.13 MV/cm

Area: 100*100 um²

Figure 3.27 (a). I-V curve of Ti/TiN/SiO2 (50nm)/PtFe/SiO2/Si structure.

Forming electrical field: 5.01 MV/cm

Voltage (V)

Area: 100*100 um²

Voltage (V)

Area: 100*100 um²

Figure 3.27 (b). I-V curve of Ti/TiN/SiO2 (30nm)/PtFe/SiO2/Si structure.

PtFe (50 nm) SiO

₂

(500 nm)

P-Si (100) TiN TiN TiN TiN TiN TiN TiN TiN TiN TiN

TiN SiO SiO

₂₂

(50nm) (50nm)

Ti

Ti Ti Ti Ti Ti

Figure 3.28 (a). Schematic diagram of Ti/TiN/SiO2/PtFe structure.

Ti (20 nm) SiO

₂

(500 nm)

P-Si (100) TiN TiN TiN TiN TiN TiN TiN TiN TiN TiN

Figure 3.28 (b). Schematic diagram of Ti/TiN/SiO2/Fe/Pt/Ti structure.

P- P -type Si type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

PtFe (50nm) PtFe (50nm) or or Ti(20nm)

Ti(20nm)\ \ Pt(80nm)\ Pt(80nm) \ Fe(5nm) Fe(5nm)

50nm PECVD oxide 50nm PECVD oxide

RCA clean RCA clean

30nm TiN and 80nm Ti deposition by 30nm TiN and 80nm Ti deposition by sputtering, then TiN

sputtering, then TiN\ \Ti patterning & etching Ti patterning & etching (100*100um

(100*100um

²²

) ) P- P -type Si type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

PtFe (50nm) PtFe (50nm) or or Ti(20nm)

Ti(20nm)\ \ Pt(80nm)\ Pt(80nm) \ Fe(5nm) Fe(5nm)

50nm PECVD oxide 50nm PECVD oxide

RCA clean RCA clean

30nm TiN and 80nm Ti deposition by 30nm TiN and 80nm Ti deposition by sputtering, then TiN

sputtering, then TiN\ \Ti patterning & etching Ti patterning & etching (100*100um

(100*100um

²²

) )

Figure 3.28 (c). Process flows of Ti/TiN/SiO2/PtFe and Ti/TiN/SiO2/Fe/Pt/Ti structures.

Voltage (V)

Area: 100*100 um²

Figure 3.29 (a). I-V curve of Ti/TiN/SiO2/PtFe structure.

Forming electrical field: 5.46 MV/cm

Voltage (V)

Area: 100*100 um²

Figure 3.29 (b). I-V curve of Ti/TiN/SiO2/Fe/Pt/Ti structure.

Voltage (V)

0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00

ln (J/V)

0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00

ln (J/V)

Figure 3.30. For PtFe and Fe bottom electrode structure, current fitting results of LRS (upper left), small bias region at HRS (lower left), and high bias region at HRS (lower

right).

Figure 3.31 (a). Statistics plot of the relationship between set (reset) voltage and different bottom electrode structures.

FePt Fe

C u rre nt ( A )

10

^-4

10

^-3

Set Reset

Figure 3.31 (b). Statistics plot of the relationship between set (reset) current and different bottom electrode structures.

FePt Fe

Power (W)

10

^-4

10

^-3

10

^-2

Set Reset

Figure 3.31 (c). Statistics plot of the relationship between set (reset) power and different bottom electrode structures.

Forming electrical field: 5.13 MV/cm

Voltage (V)

-3 -2 -1 0 1 2 3

C u rre nt ( A )

10

^-8

10

^-7

10

^-6

10

^-5

10

^-4

10

^-3

1st 2nd 3rd 10th 50th

4

1 2

3

Limit I: 5mA 100*100 um

²

Figure 3.32 (a). I-V curve of Ti/TiN/SiO2/PtFe structure (As deposition).

Endurance (times)

0 50 100 150 200 250 300

Read current @ 0.2V

10

^-6

10

^-5

10

^-4

10

^-3

HRS LRS

Figure 3.32 (b). Endurance of the Ti/TiN/SiO2/PtFe structure about 300 times (As deposition).

Voltage (V)

-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5

Curre nt ( A )

10

^-10

10

^-9

10

^-8

10

^-7

10

^-6

10

^-5

10

^-4

10

^-3

10

^-2

1st 2nd 3rd 10th 50th

4

1

2

3

Limit I: 5mA 100*100 um

²

Forming electrical field: 0.08 MV/cm

Figure 3.33 (a). I-V curve of Ti/TiN/SiO2/PtFe structure (Furnace annealing 600^oC, 30min in vacuum).

Endurance (times)

0 200 400 600 800 1000

Read current @ 0.2V 10

^-5

10

^-4

10

^-3

HRS LRS

Figure 3.33 (b). Endurance of the Ti/TiN/SiO2/PtFe structure over 1000 times (furnace annealing 600^oC, 30min in vacuum).

Voltage (V)

Forming electrical field: 1.25 MV/cm

Figure 3.34 (a). I-V curve of Ti/TiN/SiO2/PtFe structure (Rapid thermal annealing 600^oC 60s, atmospheric pressure in N2 or air condition).

Endurance (times)

0 200 400 600 800 1000

Read Current @ 0.2V

10

^-5

10

^-4

10

^-3

HRS LRS

Figure 3.34 (b). Endurance of the Ti/TiN/SiO2/PtFe structure over 1000 times (Rapid thermal annealing 600^oC 60s, atmospheric pressure in N2 or air condition).

As RTA FA (< 300 times) (> 1000 times)

Figure 3.35. Statistics plot of the relationship between HRS (LRS) reading current at 0.2V and different thermal treatment conditions.

Sputter Times (sec)

80nm Ti / 30nm TiN 50nm SiO

₂

PtFe electrode

Sputter Times (sec)

80nm Ti / 30nm TiN 50nm SiO

₂

PtFe electrode

Figure 3.36. SIMS results of Ti/TiN/SiO2/PtFe structure during RTA or FA thermal treatment.

Binding Energy (eV)

700 710

720 730

740

In ter s ity (a.u )

As-deposition FA 600oC 30min RTA 600oC 60s

Figure 3.37. XPS results of SiO2 and PtFe interface region (As-deposition, FA and RTA thermal condition).

Theta - 2 Theta

30 31 32 33 34 35

In te rsity (a.u )

As deposition FA 600oC 30min RTA 600oC 60s

Figure 3.38. XRD results of As-deposited, FA and RTA sample.

RTA FA After Forming or Set process.

Forming electrical field: 1.25 MV/cm Forming electrical field: 0.08 MV/cm

Bottom electrode

PtFe bottom electrode

(-)

Top electrode

SiO₂ (Low resistance paths) Al top electrode

(+)

Fe₂O3 (High Resistance) Bottom electrode

PtFe bottom electrode

(-)

Top electrode

SiO₂ (Low resistance paths) Al top electrode

(+)

Fe₂O3 (High Resistance)

Bottom electrode

PtFe bottom electrode

(-)

Top electrode

SiO₂ (Low resistance paths) Al top electrode

(+)

Fe₂O3 (High Resistance) Bottom electrode

PtFe bottom electrode

(-)

Top electrode

SiO₂ (Low resistance paths) Al top electrode

(+)

Fe₂O3 (High Resistance)

Figure 3.39. The possible mechanisms for FA and RTA sample after forming or set process.

Figure 3.40. Statistics plot of the relationship between set voltage and different thermal treatment conditions.

SiO

₂

(500 nm)

Figure 3.41 (a). Schematic diagram of small size Ti/TiN/SiO2/PtFe/SiO2/Si structure.

P

P- -type Si type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

50nm Fe

50nm Fe

_0.730.73

Pt Pt

_0.270.27

(composition by ICP (composition by ICP- -MS) MS)

50nm PECVD oxide deposition and 30nm TiN 50nm PECVD oxide deposition and 30nm TiN deposition by sputtering, then

deposition by sputtering, then TiN patterning & etching TiN patterning & etching RCA clean

RCA clean

200nm Via hole and 250nm contact hole, then 200nm Via hole and 250nm contact hole, then 80nm Ti lithography patterning and etching 80nm Ti lithography patterning and etching

(100um

(100um × × 100um) 100um) Rapid thermal annealing 600

Rapid thermal annealing 600

^oo

C 60s C 60s P

P- -type Si type Si (100) substrate (100) substrate

Wet oxidation (500nm) Wet oxidation (500nm)

50nm Fe

50nm Fe

_0.730.73

Pt Pt

_0.270.27

(composition by ICP (composition by ICP- -MS) MS)

50nm PECVD oxide deposition and 30nm TiN 50nm PECVD oxide deposition and 30nm TiN deposition by sputtering, then

deposition by sputtering, then TiN patterning & etching TiN patterning & etching RCA clean

RCA clean

200nm Via hole and 250nm contact hole, then 200nm Via hole and 250nm contact hole, then 80nm Ti lithography patterning and etching 80nm Ti lithography patterning and etching

(100um

(100um × × 100um) 100um) Rapid thermal annealing 600

Rapid thermal annealing 600

^oo

C 60s C 60s

Figure 3.41 (b). Process flows of Small Size Ti/TiN/SiO2/PtFe/SiO2/Si structure.

Voltage (V)

Figure 3.41 (c). I-V curve of Ti/TiN/SiO2/PtFe structure (top electrode area: 7.5um²).

Etching Time (s)

SiO ₂ Transition PtFe

Etching Time (s)

SiO ₂ Transition PtFe

Figure 3.42 (a). AES results of small size Ti/TiN/SiO2/PtFe structure.

Binding energy (eV)

Interity (a.u ) Fe(2p _3/2 )

Fe ₂ O ₃ (2p _3/2 )

Interity (a.u ) Fe(2p _3/2 )

Fe ₂ O ₃ (2p _3/2 )

Satellite

Figure 3.42 (b). XPS result between SiO2 and PtFe bottom electrode interface region.

Log (Voltage (V))

Ohmic Law (Less Temperature Sensitive)

Log (Voltage (V))

Ohmic Law (Less Temperature Sensitive)

Figure 3.43. For small size structure, current fitting results of LRS (upper left, insert shows less temperature sensitivity), small bias region at HRS (lower left), and high

bias region at HRS (lower right) (insert shows FP emission mode at difference temperature).

Size area (um2)

10 100 1000 10000

Resistance (ohm) @ 0.5 V

10

³

10 100 1000 10000

Resistance (ohm) @ 0.5 V

10

³

Figure 3.44. Statistics plot of the relationship between HRS (LRS) resistance and device size.

Figure 3.45 (a). Statistics plot of the relationship between set current density and device size.

Size (um2)

5 10 15 20 25 30

Set Voltage (V)

1.5 2.0 2.5 3.0

3.5 •Increase with area

Size (um2)

5 10 15 20 25 30

Set Voltage (V)

1.5 2.0 2.5 3.0

3.5 •Increase with area

Figure 3.45 (b). Statistics plot of the relationship between set voltage and device size.

Size (um2)

5 10 15 20 25 30

Set power per area (W/um 2 )

10

^-7

10

^-6

10

^-5

10

^-4

Independence with area

Figure 3.45 (c). Statistics plot of the relationship between set power per area and device size.

Size (um2)

5 10 15 20 25 30

Reset current (A)

10

^-3

10

^-2

Light dependence with area

Size (um2)

5 10 15 20 25 30

Reset current (A)

10

^-3

10

^-2

Light dependence with area

Figure 3.46 (a). Statistics plot of the relationship between reset current and device size.

Size (um2)

5 10 15 20 25 30

Reset Vo ltag e (V)

1.0 1.5 2.0 2.5 3.0

Independence with area

Size (um2)

5 10 15 20 25 30

Reset Vo ltag e (V)

1.0 1.5 2.0 2.5 3.0

Independence with area

Figure 3.46 (b). Statistics plot of the relationship between reset voltage and device size.

Size (um2)

5 10 15 20 25 30

Reset power (W)

10

^-3

10

^-2

Independence with area

Size (um2)

5 10 15 20 25 30

Reset power (W)

10

^-3

10

^-2

Independence with area

Figure 3.46 (c). Statistics plot of the relationship between reset power and device size.

Compliance Current (A) 0.1mA 0.5mA 1mA

0.5V read resistance (ohm) 1200

1400 1600 1800 2000 2200 2400 2600

•Area: 25 um ²

Compliance Current (A) 0.1mA 0.5mA 1mA

0.5V read resistance (ohm) 1200

1400 1600 1800 2000 2200 2400 2600

•Area: 25 um ²

Figure 3.47. Statistics plot of the relationship between 0.5V read resistance and compliance current.

Faucet total area

0.1mA 0.5mA 1mA

Compliance current

Figure 3.48. Relationship between electric faucet’s cross section area and compliance current.

Compliance current (A)

0.1mA 0.5mA 1mA

Reset Power (W)

10

^-3

•Area: 25 um ²

Compliance current (A)

0.1mA 0.5mA 1mA

Reset Power (W)

10

^-3

•Area: 25 um ²

Figure 3.49. Statistics plot of the relationship between reset power and compliance current.

Chapter 4 Conclusion

In this thesis, it has been shown that the SiO2 possesses resistive switching phenomena. We have proposed a possible model and mechanism to explain why oxygen vacancies and phase change between Fe2O3 and Fe3O4 in the Ti/TiN/SiO2/PtFe structure which presents the resistance switching behavior. Different device structures, different thermal treatments and different top electrode sizes could be explained by using the model of phase change between Fe2O3 and Fe3O4, and the amounts of oxygen vacancies.

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在文檔中 氧空缺與相變化在氮化鈦/二氧化矽/鐵白金結構電阻式非揮發性隨機存取記憶體的影響 (頁 64-0)