Non-volatile semiconductor memories have attracted much attention due to the fast growing demand of portable electronic devices. In this thesis, the atomic layer deposition prepared HfO2 thin film was fabricated with TEMAH as precursor and O2 plasma as oxidant. A 7-nm thick HfO2 thin film was applied as the charge trapping layer. The significant hysteresis loops found in C-V relation indicated the exellent charge storage effect. In additon, the erase and retention characteristics were investigated and the results were satisfactory for nonvolatile memory application.
Moreover, the Au nanocrystals were embedded in HfO2 at different locations. The effect on the device was investigated. It is found that the Au nanocrystals have an influence on the device characteristics due to the field enhancement effect.

Chapter 1 Introduction 1
1.1 Introduction 1
1.2 Research motivation 4
1.3 Thesis organization 5
Chapter 2 Literature Review 6
2.1 Introduction to semiconductor memory 6
2.2 Flash memory 9
2.2.1 Basic concept 9
2.3 Emerging nonvolatile memory 15
2.3.1 FeRAM 16
2.3.2 MRAM 18
2.3.3 PCRAM 20
2.3.4 RRAM 22
2.3.5 SONOS 24
2.3.6 SOHOS 25
2.3.7 Nanocrystal memory 26
2.4 SONOS-type memory 27
2.4.1 Operation(program/erase) mechanism 27
2.4.2 Memory characteristics of SONOS-type memory 32
2.4.3 high-k oxide as blocking oxide for SONOS-type
memory application 35
Chapter 3 Methods and Experiment 36
3.1 Experimental details and procedures 36
3.1.1 Substrate RCA clean 38
3.1.2 Back-side ion implantation 38
3.1.3Thermal oxidation of tunnel oxide (SiO2) 39
3.1.4 Deposition of HfO2 layer by ALD 39
3.1.5 Au Thin Film Deposition 41
3.1.6 Deposition of blocking oxide 42
3.1.7 Rapid thermal annealing process 44
3.1.8 Metallization 45
3.2 Analysis and Measurement 47
3.2.1 C-V measurement 47
3.2.2 Erase Curve 47
3.2.3Retention Measurement 47
Chpater 4 HfO2 as Charge Trap Layer 49
4.1 Introduction 49
4.2 Results and discussion 51
4.2.1 The charging effect in MLHOS capacitor 51
4.2.2 Erase characteristics of MLHOS capacitor 57
4.2.3Charge retention characteristics in MLHOS capacitor 58
Chapter 5 Au nanocrystal’s Field enhancement effect on
HfO2 as charge trapping layer 60
5.1Introduction 60
5.2 The effects of embedded Au nanocrystals on the
charging effect 61
5.3 The effects of embedded Au nanocrystals on the erase
characteristics 68
5.4 The effects of embedded Au nanocrystals on retention
characteristics. 71
5.5 Conclusion 75

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