Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-09T13:58:37.485Z Has data issue: false hasContentIssue false

Low Temperature Growth of Silicon Structures for Application in Flash Memory Devices

Published online by Cambridge University Press:  01 February 2011

Thomas Attia Mih
Affiliation:
[email protected], De Montfort University, Emerging Technologies Research Centre, Leicester, United Kingdom
Shashi Paul
Affiliation:
[email protected], De Montfort University, Emerging Technologies Research Centre, Hawthorn Building, The Gateway, Leicester, LE1 9BH, United Kingdom
Richard BM Cross
Affiliation:
[email protected], De Montfort University, Emerging Technologies Research Centre, The Gateway, Leicester, LE1 9BH, United Kingdom
Get access

Abstract

An in-depth study of the structural and electrical properties of silicon (Si) films deposited by a novel low temperature technique at temperatures less than 400°C in a 13.56 MHz RF PECVD reactor is reported. The method is based on substrates having to undergo some initial preparatory steps (IPS) before the deposition of Si films in the PECVD chamber. The optical band gap of Si films deposited using this novel technique narrowed to 1.25 eV from 1.78 eV using the traditional a-Si:H deposition recipe. No annealing of any form was performed on the films to attain this band gap. Furthermore, photosensitivities for these films under various deposition conditions were of order 100 compared to 104 for a-Si:H films deposited under like conditions. Using metal-insulator-semiconductor devices, the Si films grown by this novel technique exhibit charge storage and memory behaviour unlike their amorphous counterparts. However, device endurance has been found to be inadequate, probably due to the presence of some contaminants - notably interstitial oxygen - which has been found elsewhere to have adverse effects on the electrical characteristics of Si films. If well harnessed, we suggest Si structures grown by this novel growth technique could be well-suited for flash memory applications, particularly 3-D flash which requires process temperatures to be less than 400 °C.

Type
Research Article
Copyright
Copyright © Materials Research Society 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Greg Atwood; Future directions and challenges for ETox Flash memory scaling, IEEE Transactions on Device Materials Reliability Volume 4, (2004), pp. 3001–305Google Scholar
2 Park, D., Kim, K., Ryu, B.I.; “3-D nano-CMOS transistors to overcome scaling limits” in Proc. Solid-state and Integr. Circuits Technol. (2004), 1, 3435 Google Scholar
3 Koliopoulou, S., Dimitrakis, P., Goustouridis, D., Normand, P., Pearson, C., Petty, M.C., Radamson, H. and Tsoukalas, D., Microelectronic Engineering, 83, (2006), 1563 10.1016/j.mee.2006.01.235Google Scholar
4 Tsuchiya, R., Izawa, M., Kimura, S., “Prospects of Si semiconductor devices and manufacturing technologies in nanometer era”, Hitachi Review (2006), 55(2), 4655 Google Scholar
5 Paul, S. (This work will be communicated to nature; shortly).Google Scholar
6 Mih, T.A., Cross, R.B., Paul, S.; “A novel method for the growth of low temperature polycrystalline silicon for 3–D flash memory” in Materials and Technologies for 3–D Integration, edited by Roozeboom, F., Bower, C., Garrou, P., Koyanagi, M., Ramm, P. (Mater. Res. Soc. Symp. Proc. Volume 1112, Warrendale, PA, 2009) pp1112, 265–269Google Scholar
7 Langfold, A. A., Fleet, M. L., Nelson, B. P. and Marley, M.; “Infrared absorption strength and hydrogen content of hydrogenated amorphous siliconPhys. Rev. B, (1992), 45, 13367 Google Scholar
8 Müllerová, J., Jureèka, S. and Šutta, P.; “Optical characterization of polysilicon thin films for solar applications”, Solar Energy (2006), 80, 667674 Google Scholar
9 Hiraki, A.; “Impurity effects” in Amorphous semiconductor Technologies and Devices, edited by Yamakawa, Y., (Japan Annual Reviews in Electronics, Computers and Telecommunication Volume 16, North Holland 1984), pp.134148 Google Scholar
10 Torres, P., Meier, J., Flückiger, R., Kroll, U., Selvan, J. A. Anna, Keppner, H., and Shah, A.; “Device grade microcrystalline silicon owing to reduced oxygen contamination”, Appl. Phys.Lett., (1996), 69(10), 13731375 Google Scholar