Radiation effects in five volt and advanced lower voltage DRAMs

Author

Shaw, D.C. ; Swift, G.M. ; Padgett, D.J. ; Johnston, A.H.

Author_Institution

Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA

Volume

41

Issue

6

fYear

1994

Firstpage

2452

Lastpage

2458

Abstract

This work examines the effects of ionizing radiation on highly scaled DRAMs. Several 4 Mb and 16 Mb DRAMs with 5.0, 3.6, and 3.3 volt memory arrays are compared. A novel approach using memory cell retention time is introduced and applied that allows insight into the effects of radiation on individual devices within a DRAM array. Data from this new application of retention time exhibits significant changes due to ionizing radiation, even at low levels where other device parameters do not change significantly. The parameter, /spl tau/ (50%), is introduced that helps classify DRAM radiation response. Data are presented showing that there are two different damage mechanisms that affect DRAM radiation response. Finally, a relationship between threshold voltage and retention time is shown for several DRAMs.<>

Keywords

DRAM chips; failure analysis; integrated circuit reliability; integrated circuit testing; radiation effects; 16 Mbit; 3 to 5 V; 4 Mbit; DRAM radiation response; damage mechanisms; data retention time test; dynamic RAM; highly scaled DRAM; ionizing radiation; lower voltage DRAMs; memory arrays; memory cell retention time; radiation effects; threshold voltage; Circuits; History; Ionizing radiation; Laboratories; Propulsion; Radiation effects; Random access memory; Space technology; Space vehicles; Threshold voltage;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/23.340601

Filename

340601