Format Internship Weekly Report_Aug 13 2012

7/28/2019 Format Internship Weekly Report_Aug 13 2012

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Internship Weekly Report

Name: Eileen Phoan Pei Fang Department: Slicing

Report Period: August 13, 2012 to August 17,2012

Report Date: August 17, 2012

TASKS GIVEN AND COMPLETED

August 14: Multi 14mpwfr 8 FWD + 9 REV defect data compilation. According to the yield report,

several cut of the 50km spool is having high microcrack and chipping issue. Hence, verification is

to be done to analyze the performance of cut.

o Referring to the microcrack images, three affected beams do not have a clear similarity in

the microcrack pattern. Therefore, it is hard to conclude that the microcrack is related to

the wire and web condition.

7th

REV G0171D41 8th

REV 3021PE419th REV 30219C31

-Red circle region can be due to

plunger at singulator.

-Other microcrack is widely distributedof and not of a concentrated region


plunger at singulator


plunger at singulator

-blue circle region microcrack iscurrently unidentified as it does not

match any pattern from yield team

database.


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o Chipping of the affected cut for the 50km spool are summarized as below.

Beam IDWeb

ConditionYAYA chip location

Chip images

30217B11 1st Used -Chip stain is found on side A and C-V crack is found on side A

-one sided chipping is found at side B and

RR143A21 6t

Used -major chip stain

-breakage is charged as chipping


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G0171D41 7t

Rev -major stain at side A and C

-Some one sided chip is found at side A

30219C31 9th

Rev - V crack is found on A side

- Side B and D are more of one sid

chip

15 Aug: Wiresaw 020 setup for mono 14mmpwfr (prop on) 7th

reverse cut test; To prepare mono g

ingot for the cut and load into WS020 after verification of the bricks is done; The wiresaw is

properly setup.

15 Aug: WS027 web growing; WS027 will be designated to perform kerf reduction cut using 10/20

sc diamond wire; pulleys are all changed and chambers are cleaned prior to web growing; swarf is

removed from the walls and top chamber using nozzle and guide is cleaned to prevent any swarf

stick in the groove; 16 Aug: To determine the high sawmark reject of WS25. The findings are determined based on the

sawmark sample of the rejected wafer, lifetime plot and type of bricks on the web.


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RR146A21 (New web)

Front Back

RR146A52 RR146A41 RR146D41 RR146A51 RR146B51 RR146A21

64mm 213mm 219mm 82mm 190mm 226mm

Corner Edge Middle Corner Edge Edge

2

1. Coarse sawmark evenly carved across the wafer

surface; Multiple sawmark at the region

2. One obvious saw mark felt across the suface from B

to D

*saw marks appear in straight line manner

1


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3021NB61 (1st

Used)

Front Back

3021NB12 30218D32 3021NB61 30218E41 3021NH21

96mm 114mm 287mm 214mm 283mm

Edge Middle Middle Middle Edge

1. Sawmark is in slight accending pattern around the same

region

2. Sawmark is coarser at the one side and gradually

smoother towards the other

3.Sawmark is in a rather straight manner

30228A41(2nd

Used)

Front Back

30228A11 30228B81 30228A21 30228D82 30228F41 30228A41

103mm 123mm 267mm 92mm 110mm 292mm

Corner Edge Edge Edge Middle Edge

1. Saw mark is more visible in a slight deflection manner.

2. Saw mark is coarser at one end and smoother at the

other


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30228G61 (3rd

Used)

Front Back

30228G72 30228D12 30228G61 30217E811 30228G12 30228G21

61mm 138mm 293mm 67mm 135mm 292mm

Middle Edge Middle Edge Edge Middle

1. Sawmark is evenly cut into the wafer surface

2. Appear in slight deflection manner

30228G51(1st

Rev)

3022XD23 30228G31 30228D31 30228H11 3022XC72 30228G51

71mm 172mm 253mm 108mm 109mm 282mm

Middle Middle Middle Corner Middle Middle

1. Coarse sawmark at one end and smoother towards the other

2. Observable different contrast at the middle and before

sawmark region of the wafer.

17 Aug: To perform research on wiresaw related defects and to justify result with theory of cut


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mechanism, material and wire condition. Gain understanding by justifying and connecting pieces ofinformation learnt during the internship period. Meanwhile, the research also assists in decisionmaking on the factors that is to be checked and identify when abnormality occurs. Currently able torelate all defects with respect to material composition, cut mechanism and cut condition.

INCOMPLETE TASK

No Subject Reason CompletionNew Target

Date

1

NEW TASK FOR NEXT WEEK

No What

1 To summarize learning of internship

2 To verify practicality of modified clamp plate

3

4

5

6

Format Internship Weekly Report_Aug 13 2012

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