3D-MEMS Probe for Fine Pitch Probing

Transcription

1 3D-MEMS Probe for Fine Pitch Probing Ryuichiro Mori R&D Japan Electronic Materials Corp IEEE SW Test Workshop 1

2 Presentation Overview 1. Introduction JEM product overview 2. Objectives Challenges in fine pitch probing Development of 3D-MEMS probe 3. Evaluation Individual fine pitch cantilever Actual probe layout 4. Conclusions 5. Next steps 2007 IEEE SW Test Workshop 2

3 1. Introduction 2007 IEEE SW Test Workshop 3

4 JEM Product Overview MPU-Logic MB series Fine pitch Logic (SoC/LCD-driver) VS series MA series Memory CEN series Cantilever (CE series) VC series MC series Cantilever Vertical MEMS Innovation of Device- & Test- technology 2007 IEEE SW Test Workshop 4

5 Application of 3D-MEMS probe (MA) Straight 24μm pitch Staggered 20μm pitch 500μm LCD-driver 2007 IEEE SW Test Workshop 5

6 2. Objectives 2007 IEEE SW Test Workshop 6

7 Challenges in Fine Pitch Probing LCD-driver Pad pitch shrink 20μm staggered, 24μm inline Stable contact with low force Avoid gold bump damage Multi dut probing 2007 IEEE SW Test Workshop 7

8 Challenges in Fine Pitch Probing SoC Pad pitch shrink 30μm pitch Stable contact with low force Avoid pad damage Low-k CUP (Circuit Under Pad) Multi dut Probing 2007 IEEE SW Test Workshop 8

9 Development of 3D-MEMS Probe Develop fine pitch cantilever with mechanical endurance Achieve lower contact force with good contact resistance Achieve precise xyz alignment in actual probe layout 2007 IEEE SW Test Workshop 9

10 3. Evaluation 2007 IEEE SW Test Workshop 10

11 3D-MEMS Probe Process Sacrificial layer on substrate Sacrificial layer Substrate Probe on sacrificial layer Remove sacrificial layer Contact tip Probe Substrate Substrate 2007 IEEE SW Test Workshop 11

12 SEM Image of Fine Pitch Cantilever 2007 IEEE SW Test Workshop 12

13 Evaluation Items Individual fine pitch cantilever Contact force/scrub mark/ot Contact resistance Contact tip wear Actual probe layout XY alignment Planarity Actual device 2007 IEEE SW Test Workshop 13

14 Contact Force / Scrub Mark / OT Contact force(gf) Over travel(um) Max. Contact Force Min. Contact Force Scrub mark Scrub mark(um) 2007 IEEE SW Test Workshop 14

15 Cres (Ω) Contact Resistance(Au Plated Wafer) Probe Force(g) force Tip material 2007 IEEE SW Test Workshop 15 A B C D E F

16 Contact Tip Wear Contact tip abrasion(um) wear(um) Touch Down down (thousands) Contact Tip Wear 2007 IEEE SW Test Workshop 16

17 Image of Contact Tip Wear TD : 0 TD : 300,000 TD : 500,000 TD : 700,000 TD:1,000,000 No significant change was observed after 1M touchdowns (no cleaning) 2007 IEEE SW Test Workshop 17

18 Actual Probe Layout 18mm 25μm pitch staggered Total 900probes 2007 IEEE SW Test Workshop 18

19 SEM Image of Probes 2007 IEEE SW Test Workshop 19

20 XY Alignment (Initial) Target 2 Y [μm ] X [μm ] 2007 IEEE SW Test Workshop 20

21 XY Alignment (after 1M TD) Target Y [μm ] X [μm ] 2007 IEEE SW Test Workshop 21

22 Planarity (Initial) Planarity [μm ] Target Probe X position [mm] 2007 IEEE SW Test Workshop 22

23 Planarity (After 1M TD) Planarity [μm ] 10 5 Target Probe X position [mm] 2007 IEEE SW Test Workshop 23

24 Evaluation on Actual Device Prober setup was done very well. Alignment Tip recognition Planarity Contact Electrical function test was completed IEEE SW Test Workshop 24

25 4. Conclusions 2007 IEEE SW Test Workshop 25

26 Conclusions 1. Fine pitch cantilever (MA) has been developed by using the 3D-MEMS probe technology. 2. Excellent contact with low force (0.2gf) against Au plated wafer. 3. Mechanical stability over 1M touchdowns has been achieved. 4. Evaluation on the actual device has been demonstrated IEEE SW Test Workshop 26

27 5. Next Steps 2007 IEEE SW Test Workshop 27

28 Next Steps 1. Proceed the MA card into a volume production 2. Apply for SoC devices Optimize probe design, probe force, probe material, probe layout 3. Improve the assembly technology for multi-dut probing 4. Next target for LCD-driver 15μm staggered, 20μm inline 2007 IEEE SW Test Workshop 28

29 Thank You IEEE SW Test Workshop 29