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RT54SX72S SEE Test

MEC Die, 0.25 µm

BNL, August, 2001

Summary

This is a test of the RT54SX72S, 0.25 µm, MEC die.  This test was run with minimal supply voltages, 4.5/2.25/2.25 for most runs.  Higher voltages were used for SEL and antifuse rupture tests. It used the the TMRSX32_Pattern logical pattern.  For both of these K-Latch test parts, there were very few upsets in any of the shift register strings.

Package: CQFP256

Serial Nos. LAN6201, LAN6202

D/C: 0125

L/C: T25KS001

Test frequency: 1 MHz.

DUT schematics:  TMRSX32_Logic.ppt. (slight change in pinout as a result of package incompatibility between 32S and 72S).

Total Number of Flip-flops: 800 (user flip-flops).

Clock Configuration: HCLK

Ions used:

279 MeV Br-81

321 MeV I-127

Antifuse rupture: Probably detected.

SEL: not detected.

Loss of control, i.e., JTAG upset: not detected.

Since the K-Latch uses redundant structures, the angle of rotation can be critical to making an accurate measurement. This includes not only the magnitude of the angle and the range of the ion, but also the direction of the rotation. The redundant K-Latch circuits are implemented with the redundancy in the "long" direction of the die, as showed in the figure below.  We tested rotating in two directions.  The main angle, which is normally used at BNL, is rotation, and is around a vertical axis as shown below.  The second axis used was roll.  Roll is about an axis that is perpendicular to the part - that is, in the direction of the beam.

   ++++++++++++++++++++++++++++++++++++++
   +                                    +
   +               DIE                  +
   +                                    +
   +                                    +
   ++++++++++++++++++++++++++++++++++++++
   ^                 ^
   |                 |
   PIN 1             |
                     |
                     |
                     |
                     |

               axis of rotation

The beam is going directly into the screen.

Test Data

Note: Voltages in red denote either an antifuse test or a single event latchup test.

Analysis

Preliminary findings:

There were very few upsets; these flip-flops are quite hard.

Jumps in the current, which appear to be antifuse damage, were detected at just over the maximum rated voltage with Iodine, at similar incidence.  While this is still quite hard, it is not as hard as the RT54SX-series devices, 0.6 um.  Note that the commercial A54SX72A, tested during the same test session (PQFP208) had similar rupture characteristics.

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Last Revised: January 09, 2002
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