Electrical characterisation of ferroelectric field effect transistors based on ferroelectric HfO2 thin films / Ekaterina Yurchuk.

Format:

Book

Author/Creator:

Yurchuk, Ekaterina, author.

Series:

Research at NaMLab

Language:

English

Subjects (All):

Hafnium.

Ferroelectric crystals.

Physical Description:

1 online resource (x, 170 pages)

Edition:

1st ed.

Place of Publication:

Berlin : Logos Verlag, [2015]

Summary:

Long description: Ferroelectric field effect transistor (FeFET) memories based on a new type of ferroelectric material (silicon doped hafnium oxide) were studied within the scope of the present work. Utilisation of silicon doped hafnium oxide (Si:HfO raisebox-0.5ex scriptsize 2) thin films instead of conventional perovskite ferroelectrics as a functional layer in FeFETs provides compatibility to the CMOS process as well as improved device scalability. The influence of different process parameters on the properties of Si:HfO raisebox-0.5ex scriptsize 2 thin films was analysed in order to gain better insight into the occurrence of ferroelectricity in this system. A subsequent examination of the potential of this material as well as its possible limitations with the respect to the application in non-volatile memories followed. The Si:HfO raisebox-0.5ex scriptsize 2-based ferroelectric transistors that were fully integrated into the state-of-the-art high-k metal gate CMOS technology were studied in this work for the first time. The memory performance of these devices scaled down to 28 nm gate length was investigated. Special attention was paid to the charge trapping phenomenon shown to significantly affect the device behaviour.

Contents:

Intro

1 Introduction

2 Fundamentals

2.1 Non-volatile semiconductor memories

2.2 Emerging memory concepts

2.3 Ferroelectric memories

3 Characterisation methods

3.1 Memory characterisation tests

3.2 Ferroelectric memory specific characterisation tests

3.3 Trapping characterisation methods

3.4 Microstructural analyses

4 Sample description

4.1 Metal-insulator-metal capacitors

4.2 Ferroelectric field effect transistors

5 Stabilisation of the ferroelectric properties in Si:HfO2 thin films

5.1 Impact of the silicon doping

5.2 Impact of the post-metallisation anneal

5.3 Impact of the film thickness

5.4 Summary

6 Electrical properties of the ferroelectric Si:HfO2 thin films

6.1 Field cycling effect

6.2 Switching kinetics

6.3 Fatigue behaviour

6.4 Summary

7 Ferroelectric field effect transistors based on Si:HfO2 films

7.1 Effect of the silicon doping

7.2 Program and erase operation

7.3 Retention behaviour

7.4 Endurance properties

7.5 Impact of scaling on the device performance

7.6 Summary

8 Trapping effects in Si:HfO2-based FeFETs

8.1 Trapping kinetics of the bulk Si:HfO2 traps

8.2 Detrapping kinetics of the bulk Si:HfO2 traps

8.3 Impact of trapping on the FeFET performance

8.4 Modified approach for erase operation

8.5 Summary

9 Summary and Outlook.

Notes:

PublicationDate: 20150630

Description based on print version record.

ISBN:

3-8325-9478-7

9783832594787