Additive Circuit Technology Roadmap for HDD Suspension

Transcription

1 Additive Circuit Technology Roadmap for HDD Suspension Speaker: Hitoki KANAGAWA Prepared by Y.Ooyabu Approved by T.Visit (PhD) NOTE; The contents of this data sheet are the exclusive property of NITTO DENKO Corp. Prior permission must be obtained for any use of these contents for purposes outside of that intend by NITTO DENKO Corp. Any question on this should be addressed to Product Development section, Printed Circuits Div., Electronic Materials Business Sector, of NITTO DENKO Corp. or local NITTO DENKO office

2 NITTO Product portfolio Protect Products Electrical Insulating Tape Double Coated Tape Sealing Materials Fibre Reinforced Plastics Medical Products Flexible Printed Circuits Circuit technology DURATACK labels Bandoliering Tapes Corrosion Protection Wafer Tapes Polarising Films Moulding Compounds NITOFLON Tapes TEMISH Products With more than 4,000 products, Nitto is available to support Electronics business with our products. In Flexible Printed Circuit division we can support using Subtractive technology and Additive technology.

3 Line-up Additive Circuit Technology Additive Circuit Technology v.s HDD Roadmap Capability of additive technology Next challenges of additive technology

4 Additive Circuit Technology Additive Circuit Technology v.s HDD Roadmap Capability of additive technology Next challenges of additive technology

5 Process comparison of both technology Additive technology Photo-resist Lamination Photo-resist imaging Sputter Seed Layer (submicron level) Photo resist Polyimide film SST Subtractive technology Copper Plating Photo-resist Lamination Sputter Seed Layer (submicron level) Plated Copper Polyimide film SST Photo resist Copper Plating Copper Plating Photo-resist Imaging Photo-resist Removing Etching of Plated Copper Etching of Sputtered Seed Layer Important point is Additive is stack up, Subtractive is etch out. Photo-resist Removing Etching of Sputtered Seed Layer

6 Advantages of additive Conductors Subtractive Conductors Top width Additive Conductors Copper Copper Cross section Conductor Width (um) Polyimide Subtractive method P r o d u c t L o t # Additive method Polyimide Subtractive technology leads to irregular conductor geometry at fine conductor line / spacing. This impacts: 1) Impedance Control 2) Ability to achieve conductor lines with < 35 um pitch.

7 Additive Circuit Technology Additive Circuit Technology v.s HDD Roadmap Capability of additive technology Next challenges of additive technology

8 HDD Trend Fly height and Areal density Areal Density[Gb/in2] Transmission Frequency Transmission Frequency[GHz] Areal Density[Gb/in2] Signal Grounding Required Server Frequency[GHz] 2.5" Frequency[GHz] Flyheight[nm] 3.5" Frequency[GHz] Fly height[nm] Areal Density[bit/inch 2 ] Areal Density Trends 1.00E+13 1T 1.00E G 1.00E+11 10G 1.00E+10 1G 1.00E+09 Thin Film Head 1.00E M Longitudinal 10M Media E+07 ADGR:30% ADGR:60% ADGR:100% GMR Head MR Head Advanced GMR Head Year Roadmap - Areal Density Continues to be enabled by PMR! - Lower fly-height require low gimbal stiffness - High frequency transmission circuit Additive is a Must!! TMR/PMR Head Perpendicular Media

9 Roadmap Circuit Write and Read technology W r i t e Read TFC TMR Head Low Fly height, High Speed Data Transmission 75Gb/in 2 Requirement for Circuit Patterned Perpendicular media recoding recording Heat assisted magnetic recording Dual Stage Actuator CPP Head 150Gb/in 2 300Gb/in 2 600Gb/in Gb/in Gb/in 2 1. Miniaturization(4 6 8~11trace) Finer Line and Space by Additive technology 2. High Frequency signal(electrical performance) Ground Plane by Additive technology

10 Nitto Roadmap Mass Production level Prototypes level Sample production level Trace Width and Spacing Items Grounding Pad 20 /20 um 15 /15 um CQ1 CQ2 CQ3 CQ4 CQ1 CQ2 CQ3 CQ4 CQ1 CQ2 CQ3 CQ4 Grounding Plane SST thickness Conductor thickness 18 um 15 um Min. 12um Min. 10um Min. 8um

11 Additive Circuit Technology Additive Circuit Technology v.s HDD Roadmap Capability of additive technology Next challenges of additive technology

12 Nitto Additive capability Line/Space Line/Space 40/40um 40/40um Trace width history of SUSPENSION Hair(100um) 30/30um 30/30um 20/20um 20/20um 15/15um 15/15um Nitto Technology Pitch 30um 25um 20um Line 15um 12um 12um 10um Space 15um 18um 13um 10um Cross section Nitto s s finer trace capability using Additive technology covers entire SUSPENSION trace width requirement!!!

13 Ground Plane Field coupling to the ground plane. SST Ground Plane Polyimide Electric Field Coupling + - Ground Plane(SST) Ground Plane GND Plane SST SST Conductivity (S/m) SST 1.1* * Ground Plane has current due to electric field coupling. These current leads to power loss. - Power loss is reduced if conductivity of ground layer is high. Ground Plane is most feasible solution for minimizing LOSSES.

14 Cross section of actual sample Basic structure-1 Ground Plane SST Trace Polyimide Basic structure-2 Skin Polyimide SST etching is available due to Skin PI Trace Trace Space (15um) Trace (15um) SST Ground Plane Skin PI Base PI Ground Plane Nitto has PI coating technology which enable us to make SST hole under the Ground Plane. It is a Must for efficient Impedance control.

15 Measurement result(transmission characteristic) Sdd21 (Transmission Characteristic) [db] Sample :: Nitto Test Coupon Line and Space :30/30um Equipment :VNA, TDR w/o GND-Plane GND-Plane-Sample2 S-Parameter w/o GND Plane GND Plane Frequency [GHz] GND-Plane-Sample-1 GND Plane-Sample3 Differential Impedance [Ω] Time Domain Reflectmetory w/o GND Plane GND Plane w/o GND plane GND Plane-Sample1 GND Plane-Sample2 GND Plane-Sample Distance from Probing Point [mm] Ground Plane shows 1) Improved signal transmission. 2) Better impedance control.

16 Additive Circuit Technology Additive Circuit Technology v.s HDD Roadmap Capability of additive technology Next challenges of additive technology

17 Next challenges of additive technology Robustness Better Subtractive Better mechanical property High conductivity by pure Copper plating Finer Line and Spacing Additive Product Design flexibility Better Product Performance

18 Stress Relaxation of Copper Foil Rolled Annealed Electrodeposited H.D. Merchant, Gould Electronics, 1997 It has been well established that Electrodeposited Copper is not as strong as Rolled Annealed Copper due to the difference in grain structure and defect concentrations

19 Nitto Denko High strength Copper Strain Relaxation (%) Conventional ED High Strength ED Nitto Denko has been developing new process technology to produce high strength high performance electrodeposited copper to meet the Fine Line / Spacing of HDD roadmap and the robustness requirement

20 Nitto Denko High strength Copper Trace Damage [%] 10.0% 7.5% 5.0% 2.5% Condition Sample: Time: Frequency: Conventional ED Copper, High Strength ED Copper 10min/20min/30min 132kHz Conventional ED copper w/o Cover PI after 30 mins Test 0.0% 10min 20min 30min 10min 20min 30min Conventional ED High strength ED By exposing copper trace to ultrasonic DI water cleaning, conventional ED copper begins to show cavitation damages after 20 mins while high strength ED copper shows no damages even after 30 mins. High Strength ED copper w/o Cover PI after 30 mins Test

21 Conclusion Nitto Denko 30 um fine line / spacing Additive Technology is ready to enable the most demanding HDD roadmap in the market. We are the only supplier of multi-layer conductor line to serve high frequency transmission rate. Higher robustness is required for additive technology associated with electrodeposited copper. Nitto Denko believes that our recent development of high strength copper will meet the most demanding mechanical requirement needed to continuously support the HDD roadmap.

22 Thank you very much for your attention.