臺灣博碩士論文加值系統

本篇論文中,我們有系統的討論氮氣快速退火對化學氣相沈積的氧化層在複晶矽介電質的特性影響,研究結果得知,原本結構較為鬆散的氧化層經過氮氣快速熱退火後有著較佳的電性,而隨著溫度的升高特性也隨之改善,但若時間太長,特性有劣化的現像產生。
其次,我們研究底層複晶矽處理對複晶矽介電層的影響,首先,我們利用氮氣快速退火來改善複晶矽的品質,經過處理後成長的氧化層有著較佳的特性,最後,我們利用成長一層薄多晶矽層在底層上, 利用多晶矽較平滑的表面來成長氧化層,可得知,長在薄多晶矽上的介電層有著較高的崩潰電荷, 較高的崩潰電場。

In this thesis, we investigate the effects of rapid post-deposition annealing (PDA) on the characteristics of TEOS deposited polyoxides ~ 11.0nm, were systematically studied with respect to PDA temperature, time, and temperature ramp rate. The results indicate that the higher annealing temperature got the better electrical characteristics and a suitable choice of PDA time will be important to obtain high quality polyoxides. To improve oxide quality, long PDA time treatment should be avoided as possible.
Finally, we study the effects of several pre-oxidation treatment technologies, including pre-oxidation nitrogen RTA, oxidizing thin recrystallized-polysilicon film on poly-1, oxidizing thin amorphous film on poly-1 on polyoxides. The obtained polyoxide has the desirable electrical characteristics of lower leakage current and higher breakdown field than those of polyoxide as-grown. At the same time, the oxides grown on treated-polysilicon have lower electron trapping rates and larger charge-to-breakdown, both attributable to their smoother polyoxide/poly-1interface than those of polyoxides as-grown.

ENGLISH ABSTRACT.................................................................................................................................I
CHINESE ABSTRACT............................................................................................................................... II
CONTENTS ...............................................................................................................................................III
TABLE CAPTIONS ....................................................................................................................................V
FIGURE CAPTIONS .................................................................................................................................VI
CHAPTER 1 ................................................................................................................................................1
INTRODUCTION ........................................................................................................................................1
1.1 BACKGROUND ....................................................................................................................................1
1.2 MOTIVATION .......................................................................................................................................2
1.3 MEASUREMENT ..................................................................................................................................3
1.3.1 Breakdown Field (Ebd) .......................................................................................................................3
1.3.2 Critical Electric Field (C.E.F) ..............................................................................................................3
1.3.3 Charge-to-Breakdown level (Qbd) ......................................................................................................4
1.3.4 Barrier Height (Fb) ..............................................................................................................................4
1.3.5 Charge Trapping Centroid (Xt) and Trapped Charge Density (Qt) ......................................................4
1.3.6 Gate Voltage Shifts (DVg) ..................................................................................................................5
1.3.7 Atomic Force Microscope (AFM) .......................................................................................................5
1.3.8 SIMS Analysis ....................................................................................................................................5
1.4 ORGANIZATION OF THIS THESIS .....................................................................................................5
CHAPTER 2 ................................................................................................................................................7
IMPROVEMENTS OF THE CVD-DEPOSITED TEOS POLYOXIDE CHARACTERISTICS WITH NITROGEN RAPID THERMAL ANNEALING............................................................................................................................7
2.1 INTRODUCTION ..................................................................................................................................7
2.2 EXPERIMENTAL DETAILS AND MEASUREMENT ..........................................................................8
2.2.1 Rapid Thermal Processing System ......................................................................................................8
2.2.2 Sample Preparation .............................................................................................................................9
2.3 RESULTS AND DISCUSSION .............................................................................................................10
2.3.1 The Characteristics of Polyoxides Grown by TEOS Oxides and Thermal Oxides ..............................10
2.3.2 The Effect of Nitrogen RTA Temperature on the CVD-deposited TEOS Oxide Characteristics .........11
2.3.3 The Effect of RTN2 Duration on CVD-deposited TEOS Oxides........................................................13
2.2.4 The Effects of RTN2 Temperature Ramp Rate on CVD-deposited Polyloxides .................................15
2.4 SUMMARY ..........................................................................................................................................15
CHAPTER 3 ...............................................................................................................................................17
THE EFFECT OF BOTTOM POLYSILICON TREATMENT ON DILUTE O2 - GROWN POLYOXIDES .17
3.1 INTRODUCTION ................................................................................................................................17
3.2 SAMPLE PREPARATION AND MEASUREMENTS ...........................................................................18
3.3 RESULTS AND DISCUSSION ............................................................................................................19
3.3.1 The Characteristics of Bottom Polysilicon RTN2 on Dilute O2-grown Polyoxides ............................19
3.3.2 The Characteristics of the Dilute O2-grown Polyoxide by Recrystallized-polyslilcon Method ...........21
3.3.3 The Characteristics of Polysilicon Oxide Grown on Thin Amorphous Silicon Deposited on Polysilicon ..22
3.4 SUMMARY ..........................................................................................................................................23
CHAPTER 4 ...............................................................................................................................................25
CONCLUSION ...........................................................................................................................................25
REFERENCES ............................................................................................................................................27

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