Laser Restructurable Technology and Design

Raffel, J.I.; Anderson, Allan; Chapman, Glenn H.

doi:10.1007/978-1-4613-1621-3_7

Cited by 28 publications

(12 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The important advantage of laser linking over transistor switches is that the result is permanent and of lower impedance than the bidirectional transistor switches[l3]. Laser link defect avoidance has built fully operational Wafer scale circuits in 6 different designs applied to DSP filter and speech recognition systems [3,4], These were packaged using large multichip module type metal packages.…”

Section: Laser Link Defect Avoidancementioning

confidence: 99%

See 1 more Smart Citation

Laser correcting defects to create transparent routing for large area FPGA's

Chapman

Dufort

1997

Proceedings of the 1997 ACM Fifth International Symposium on Field-Programmable Gate Arrays - FPGA '97

View full text Add to dashboard Cite

Creating large area FPGA's is limited by the presence of defective sections. The techniques developed in wafer scale work solve this problem by using defect avoidance routing around flawed blocks to build complete working systems. FPGA's have the main features required for successful defect avoidance systems: a repeatable cell, built in need for switchable flexible routing and high fiexibility with potentially large number of applications. Laser formed connections and cuts have proved to be effective in bypassing fabrication time defects and creating defect free working systems up to wafer scale in area. Power shorts and clock distribution errors can effectively be eliminated using these laser links. In addition it is important to minimize signal delays so the bypassing of the defective cells is nearly invisible. Experiments on a small test FPGA shows defect avoidance routing using laser link structures generates delays which are about half those obtained by the active switches required for the FPGA's operation. Thus laser defect avoidance after fabrication removes the errors creating a large area FPGA whose defective cell distribution is nearly unseen by the user.

show abstract

Section: Laser Link Defect Avoidancementioning

confidence: 99%

“…In commercial devices, such as DRAM's with areas of about 15x15 mm, this has lead to significantly enhanced yields. In more experimental applications laser defect avoidance has expanded usable silicon real estate into Wafer Scale Integration (WSI) device areas 25 square centimeters [3] [4].…”

Section: Introductionmentioning

confidence: 99%

Laser correcting defects to create transparent routing for large area FPGA's

Chapman

Dufort

1997

Proceedings of the 1997 ACM Fifth International Symposium on Field-Programmable Gate Arrays - FPGA '97

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

“…Specifically, this means the ability to integrate laser restructurable elements with standard CMOS processing [3,6]. Diffused links [6,7], which involve conduction through the silicon, have been used for some time to achieve this compatibility goal. More recently, direct metal-to-metal connections were made on structures fabricated with standard CMOS processing [8] where links were formed when a laser was focussed on the metal 1 through an annular region of metal 2, but the linking yield was never shown to be better than 99%.…”

Section: Introductionmentioning

confidence: 99%

<title>Laser-induced microfracture leading to high-density metal-to-metal connections</title>

1994

View full text Add to dashboard Cite

keywords : laser, repair, interconnect, metal, link AB STRACT Laser programmed inter-level metal connections have been developed as a means to achieve high density linking for customization in programmable gate arrays and for additive redundancy in restructurable integrated circuits. This work reports on the linking of 4 x 4 pm crossings of standard two-level metal interconnect lines and subsequent microstructural analyses aimed at understanding the mechanism of link formation. The links were formed by focusing a laser on metal 1 through an annular region of metal 2. The mechanism of link formation appears to be a physical connection made by a fracture of the inter-level dielectric (ILD) layer due to the stress of thermal expansion of the metallization with molten metal 2 filling the crack. Focussed ion-beam (FIB) cross sectional micrography and finite element analysis (FEA) have allowed us to analyze the successfully formed links as well as the failures to link. As a result of our analysis, we have begun to understand how to optimize the device geometry for very high reliability laser linking.

show abstract

“…Six RVLSI systems have been built on three different wafer designs [2] with the largest one having 405K functional transistors. One Integmtor wafer has been operating in a bench tester for 4 1/2 years without failure.…”

Section: K R O T a T I O N Smentioning

confidence: 99%