Low-power and high-stability SRAM technology using a laser-recrystallized p-channel SOI MOSFET

Author

Takao, Yoshihiro ; Shimada, Hiroshi ; Suzuki, Noriyuki ; Matsukawa, Yoshihiro ; Sasaki, Nobuo

Author_Institution

Fujitsu Ltd., Kawasaki, Japan

Volume

39

Issue

9

fYear

1992

fDate

9/1/1992 12:00:00 AM

Firstpage

2147

Lastpage

2152

Abstract

Laser recrystallization of p-channel SOI MOSFETs on an undulated insulating layer is demonstrated for SRAMs with low power and high stability. Self-aligned p-channel SOI MOSFETs for loads are stacked over bottom n-channel bulk MOSFETs for both drivers and transfer gates. A sufficient laser power assures the same leakage currents between SOI MOSFETs fabricated on an undulated insulating layer in memory cell regions and on an even insulating layer in field regions. The on/off ratio of the SOI MOSFETs is increased by a factor of 10⁴, and the source-drain leakage current is decreased by a factor of 10-10² compared with those of polysilicon thin-film transistors (TFTs) fabricated by using low-temperature regrowth of amorphous silicon. A test 256-kb SRAM fabricated this technology shows improved stand-by power dissipation and cell stability. The process steps can be decreased to 83% of those TFT load SRAMs if both the peripheral circuit and memory cells are made with p-channel SOI and n-channel bulk MOSFETs

Keywords

MOS integrated circuits; SRAM chips; VLSI; insulated gate field effect transistors; integrated circuit technology; laser beam annealing; recrystallisation annealing; 256 kbit; 3D SRAM cell; SRAM technology; Si-SiO₂; cell stability; high stability; laser recrystallization; leakage currents; low power; n-channel bulk MOSFETs; on/off ratio; p-channel SOI MOSFETs; process steps reduction; self aligned MOSFETs; stand-by power dissipation; undulating insulating layer; Amorphous silicon; Circuit testing; Insulation; Laser stability; Leakage current; MOSFETs; Power lasers; Random access memory; Silicon on insulator technology; Thin film transistors;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.155886

Filename

155886