T-Flex Yield Improvementftqm.or.th/images/document/symposium/2019-20/... · Mektec Manufacturing Corporation (Thailand) Ltd. Supporting the Global Electronics society. Mektec is the

(ชือ่บรษิทั) 1

T-Flex Yield Improvement

www.mektec.co.th

1/25

By Six Sigma

Mektec Manufacturing Corporation (Thailand) Ltd.2/25

Mektec Manufacturing Corporation (Thailand) Ltd.

Supporting the Global Electronics society.

Mektec is the leader of Flexible printed circuits manufacturer, providing to our valuable customer through worldwide sales and manufacturing bases.

Space-saving design.

3/25



0.3

2%

0.2

0%

0.1

9%

0.1

8%

0.1

7%

0.1

6%

0.1

0%

0.1

0%

0.0

8%

0.0

7%

0.0

6%

97.50%

98.00%

98.50%

99.00%

99.50%

100.00%

0.00%

0.05%

0.10%

0.15%

0.20%

0.25%

0.30%

0.35%

WRK OTP OTB FMS PLT OTF FME FNF OTA PLI MRP

%D

efe

ctiv

e.

Defective Rate all model of GC-assembly on Jun'18

Defect (%) Yield (%)

A86 T-flex demand 35% of GC-AS

WRK defect top of GC-AS

WRK. is top defective about 0.32% In Jun’18.

Model A86 T-Flex is top demand in Jul – Dec’18.

5/25


3.28% 3.28% 3.26%2.77%

2.01% 1.87%1.34%

0.98% 0.76%

0.00%

0.50%

1.00%

1.50%

2.00%

2.50%

3.00%

3.50%

A86 T-Flex A85 T-Flex E72A DISPLAY A62 U-Flex A72 U-Flex A61 U-Flex A41 T-FLEX A51 D-FLEX A71 U-Flex

Def

ectv

e ra

te

Product

GC Top defective rate in Jun'18In put =1257251 Pcs.Yield = 96.7%.Defective rate of WRK = 0.85%

A86 T-Flex is highest volume in Jul–Dec’18.

WRK. is top defective about 0.85% In Jun’18.

6/25


1.45%

0.90%

1.34%

0.79%

1.11%

0.74%

0.57%

1.10%

0.68%

0.99%

0.67%

0.95%0.98%

0.75%0.81%0.84%

1.40%

1.21%

0.76%0.68%

0.73%0.68%

0.58%

0.92%

0.69%

0.94%

0.59%

0.80%0.74%

0.00%

0.20%

0.40%

0.60%

0.80%

1.00%

1.20%

1.40%

1.60%

0

20

40

60

80

100

120

1-J

un

2-J

un

3-J

un

4-J

un

5-J

un

6-J

un

7-J

un

8-Ju

n

9-J

un

10

-Ju

n

11

-Ju

n

12

-Ju

n

13

-Ju

n

14

-Ju

n

15

-Ju

n

16-J

un

17

-Ju

n

18

-Ju

n

19

-Ju

n

20

-Ju

n

21

-Ju

n

22

-Ju

n

23

-Ju

n

24

-Ju

n

25

-Ju

n

26

-Ju

n

27

-Ju

n

28

-Ju

n

29

-Ju

n

30

-Ju

n

Per

cen

t

Kp

cs.

Date

A86 T-Flex WRK by daily on Jun'18

Out Put %WRK Base Line Target

In Jun’18 …Found WRK defect at A86 T-flex model average about 0.85%.Target reduce 70% from 0.85% to 0.25% with in ww.33 or reduce 44% from base point.

Goal : To improvement each activities more than 70% from base line in defective WRK (1 month).

70% improve

7/25


- -

1,244 1,460 1,690

598 - -

1,744

2,988

4,447

6,137 6,735

-

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

-

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

Jun Jul Aug Sep Oct Nov Dec

KTH

B.

KP

CS.

MONTH

A86 T-Flex Demand and Cost Saving.Demand Cost saving Cumulative cost saving.

Current status A86 T-Flex is highest demand of B product from Jun-Dec’18. A86 T-Flex found high WRK defective rate in Jun’18 about 0.85%. GC target reduce 70% from 0.85% to 0.25% with in ww.33.

Cost saving plan all project is 6.74 Mthb.

Refer to Demand in Jun’18

8/25


> 95% < 0% < 5%

7 14371 100% 0.0% 0.0%

8 13839 100% 0.0% 0.0%

18 11039 100% 0.0% 0.0%

No. EN. Effectiveness Miss Rate False Alarm Rate

Retrain and Result re-test.

GR&R for criteria WRK. only. Re train and retest inspector who not achieved target. GR&R Test every month.

Pass 100%

Date of study:

Reported by:

Name of product:

Misc:

2019181716151413121110987654321

100

95

90

85

Appraiser

Percen

t

95.0% CI

Percent

2019181716151413121110987654321

100

95

90

85

Appraiser

Percen

t

95.0% CI

Percent

Assessment Agreement

Within Appraisers Appraiser vs Standard

9/25


Short termimprovement

Long term

improvement

Standardize

& Implement for next model

Defects analysis- Repeat again.- Actions by case .

Apply Automation- Auto FPC set robot.- Auto FCT robot.- Auto flip tray.

Set standardize and Implement for next model.

Step 1 Step 2 Step 3

10/25


0.00% 0.00% 0.00% 0.00%0.14%

0.00% 0.00% 0.00%

0.59%

0.00% 0.00%0.00%

0.10%

0.20%

0.30%

0.40%

0.50%

0.60%

0.70%

%D

efe

ctiv

e

Process mapping A86

Oven dry

FPC setRemov

eUnder

fillPre-

blankPSA

Press PSA

Blank#2

FCT FinalPackin

g

Process mapping summary.

1. Raw mat’l (1.13%) : Before process take action.

2. Pre-blanking (0.14%) : Auto remove , Auto blank and Auto set PSA.

3. FCT (0.59%) : Flip tray , guide out line and method FCT. Focus 2 Process.

11/25


Assumption: Load FPCA Misalignment with Test Fixture effect to WRK.

Root cause Analysis 1. FCT. Load FPCA misalignment with Fixture.

Fish bone analysisVDO

Current situation.

1.Place in Test Fixture but not fit.

ACF area miss position

2. FPCA bend 0⁰- <90⁰ after FCT WRK reject.

90⁰120⁰ 45⁰ WRK

FPCAFixture FCT (Botton)

Fixture FCT (Top)

90⁰120⁰ 45⁰

Mapping from NG unit.

80% Rej. ACF Area

Next Evaluate working methodin action step.

12/25


Assumption : FPCA overlap and jump out from pocket tray effect to WRK.

Root cause Analysis 2. FCT. FPCA overlap from flip tray.Current situation.

To compare flip tray FPCA overlap vs flip tray FPCA not overlap >> Testing to FCT (FPCA overlap : Warpage ≥ 90⁰).

0.54%

0.00%0.00%

0.10%

0.20%

0.30%

0.40%

0.50%

0.60%

FPCA hit flip tray. FPCA not hit flip tray.

% D

efec

tive

.

Compare Defective WRK.

% Defective.

Prepare FPC by no overlap in

tray

Back : Flip test

Current design

Front : tray blank

Next : Tray improvement in action step.

13/25


Root cause Analysis 2. Pre-blank Misalignment loading at PSA Fixture and press by cover PSA fixture.Current situation.

Assumption : Misalignment loading at PSA Fixture effect to WRK.

To compare FPCA sheet misalignment load at FPC Set vs Loading correctly.

FPC Sheet move.

misalignment

WRK

Why Why analysis Misalignment loading.

0.14%

0.01%

Misalignment Not Misalignment

Compare defective.

Next : Improve loading to PSA fixture method in action step.

14/25


Cause Result after test Action

1. FCT : Load FPCA Misalignment with Fixture.

Significant Evaluate working method.

2. FCT : FPCA overlap in tray. Significant Tray improvement.

3. Pre Blank : Misalignment loading at PSA Fixture and press by cover PSA fixture.

Significant Improve loading to PSA fixture method.

15/25


Find out area to pick up FPCA for load to Test Fixture.

35

4

1 2

Study loading method to test Fixture.

Method1 : Pick up area point 1.

Method2 : Pick up area point 2.

Method1 : Can’t find target.Method2 : Significantly.Method3 : No loading target and Ergonomic problem.Method4 : Ergonomic problem and Wrist cuff pick up.Method5 : Significantly.

Method2 : Control totter ACF area.

Method 3 : Pick up area point 3.



1

1

16/25


We select Sample size 3,200 pcs.Sample size

3191

Compare result

Control totter ACF area ACF area miss position

Significantly Not Significantly

Method 2 Method 5

17/25


Tray improvement.

New design flip tray : Current Flip tray design use 2 side of tray for Flip , New design separate to 2 tray and have 2 step.

Blank tray

Test flip tray

New design

Design difference pocket height each cavity to avoid ACF damage.

1.10%

0.00%0.00%

0.20%

0.40%

0.60%

0.80%

1.00%

1.20%

Current design New design

% D

efec

tive

.

Compare design

%ACF งอ

Compare result

18/25


2. Problem : Vacuum pad not enough. Action : Add vacuum rain tree from 6 set to 8 set.

1. Problem : No guild pin lock FPC. Action : Add pin POKAYOKE on set PSA.

0.14%

0.07%

0.00%

0.02%

0.04%

0.06%

0.08%

0.10%

0.12%

0.14%

0.16%

Current New

% D

efe

ctiv

e.

Compare Defective WRK.

Current New

Compare result

3. Problem : Not set STD vacuum force. Set standard vacuum force (45-85 kPa).

Vacuum WRK Drop Can't vacuum Status

40 kPa 0.00% 0.00% 100.00% NG

45-85 kPa 0.00% 0.00% 0.00% OK

90 kPa 37.50% 5.00% 9.00% NG

19/25

FCT action

Pre-blank action

Change Tray flip



Refer : TI-PIN-1063 (Pre-blank)TI-PIN-1254 (Tray&FCT)

ตารางตรวจสอบความพรอ้มกอ่นเริม่ท าการผลติ

MODELA86 T-Flex OPERATION :ตัว

อยา่ง

DATE /

MONTH6 / 7

- -

LINE NO. JC1

M/C. NO. 08

SHIFT A

TIME 1430

MODE CS

1 Vacuum pad Arm pick up FPC

8 Set

ดทูี ่vacuum arm O หรอื X OPERATOR O

2 Vacuum pad Arm pick up FPC

8 Point

ดตู าแหน่งที ่vacuum arm ดดู

FPCO หรอื X OPERATOR O

3 Pin on base FPC set

4 Pin

ดจู านวน Pin ที ่Base O หรอื X OPERATOR O

4 Vacuum value 45 to 85 kPa ดหูนา้จอก าหนดลม O หรอื X OPERATOR x

4 Machine safety ปุ่ ม Emergency

ปุ่ ม Emergency

ตอ้งอยูใ่นสภาพไมแ่ตกหัก

เมือ่กดปุ่ มเครือ่งตอ้งหยดุท างาน

ทันที

O หรอื X OPERATOR O

5 PM Over Due PM ตอ้งไม ่Over Due ดทูีส่ติ๊กเกอร ์PM O หรอื X OPERATOR O

CHECK BY EN NO. OPERATOR B456

CHECK BY EN NO. TECHNICIAN B123

JUDGEMENT BY OKหรอืNG OK

DAILY AUDIT BY EN NO. B100

WEEKLY AUDIT BY Signature PROD MGR

QA Audit Acc / Rej QA Auditor A หรอื R

ASSIS SUPV

/ SUPV.

DAILY CHECK SHEET

Auto set PSA OPERATION CODE :3420 M/C NAME : YEAR :

NOTE :

รายการ จดุตรวจสอบ ขอ้ก าหนด วธิตีรวจสอบวธิี

บนัทกึคา่

ระเบยีบปฏบิตั/ิ ข ัน้ตอนการปฏบิตั ิ(Methodology)In-process tray flip ม ี2 แบบ คอื In-process tray blanking และ In-process tray FCT

1. ใหใ้ช ้Code MPCT 054A (Blank) และ code MPCT 054B (FCT) (ยกเลกิใช ้code MPCT 029)

2. ท ำกำร flip tray โดยกำรจับดำ้นขำ้งของ tray แลว้พลกิ tray กลับดำ้นเพือ่ใหต้ัวงำนมำอยู่ที ่Tray FCT

3. ใช ้Vacuum pen จับตัวงำนบรเิวณจดุกึง่กลำงของ FPCA (ใต ้shim)

4. Load งำนเขำ้ fixture FCT โดยใหก้ะระยะจำก Outline เมือ่ FPC ชดิกับ Outline

ดำ้นหลังแลว้ใหป้ลอ่ยงำนลง โดยไมต่อ้งกดตัวงำนลงไป เพือ่หลกีเลีย่งกำรชนของ ACF

In-process tray Blanking: MPCT A In-process tray FCT: MPCT B

Logo Mektec

Old design code : MPCT 029

pick up

Outline Outline

21/25


Before After

1. Auto FPC set robot.

2. Auto FCT robot.

3. Auto flip tray.

22/25


Cost saving.

0

1744

2988

4447

61376735

1,330

4,273

5,802

7,226

9,13910,017

0

2000

4000

6000

8000

10000

12000

Jul'18 Aug'18 Sep'18 Oct'18 Nov'18 Dec'18

Savi

ng

KTh

b.

Month.

Cost saving.(KThb)

Plan Actual Cum Plan Saving Cum Actual Saving

In Jul-Dec’18 saving cost about 10 MThB.

Δ +10.0 MThB (Jul-dec’18).

Start

23/25


0.44%

0.69%

0.61% 0.63%0.60%

0.62%

0.74%

0.00%

0.11%0.10% 0.10%

0.23%

0.17%

0.23%

0.00%

0.10%

0.20%

0.30%

0.40%

0.50%

0.60%

0.70%

0.80%

0

100

200

300

400

500

600

ww.23 ww.24 ww.25 ww.26 ww.27 ww.28 ww.29 ww.30 ww.31 ww.32 ww.33 ww.34 ww.35 ww.36

%

Kp

cs.

A85T-flex : Monitor WRK

Out Put %WRK. Target

1st expand to model A85 T-flex.

We can reduce WRK defective of A85 T-Flex from 0.60% in Jun’18 to less than

0.25% in Aug’18.

Stop build change Design.

24/25

Q & A

25/25

Documents

T-Flex Yield Improvementftqm.or.th/images/document/symposium/2019-20/... · Mektec Manufacturing Corporation (Thailand) Ltd. Supporting the Global Electronics society. Mektec is the