1. ADVANTEST EB F5112+VD01 (Best for Nanotech) Seminar
２００５年３月
MITA Yoshio
Produced by SML Team MEMS MITA Yoshio, KUBOTA Masanori, Kota ITO

2. Machine Specification
Accel: 50kV , Max dose 120μC/cm2
Originally 8-inch wafer direct writer
Very rapid: takes less than 1h for entire 4inch
VDEC special version: 2,3,4inch round wafer, 4,5inch masks, 1～3cm cut wafers.
Field discontinuity 3σerror： Sub field 20nm, Main field50nm
Main Field: 1.6mm×0.8mm
Sub Field:80μm□ x y
Pattern

3. Finalized photomask View from CrO2 side
Exposure example
No optimization. Just a simple exposure gives..
Too fine to evaluate..
０．２
０．３
０．４
０．５
０．６
０．７
０．８
０．９
Resist on SiO2
Finalized photomask View from CrO2 side １
Resist ZEP-520A 4000rpm 60s Prebake180℃15min, 80µC/cm2 Dev: ZED-N50 96s （ドースは100前後、現像3分前後がよいという説も有。詳細はこれから）
ToppanST TLR6 TQZ T EBR9 HS31 7.0µC/cm2、Dev: 23℃230s, Ashing 20s, etching70s Undercut from both 0.1µ because of wet etching.

4. What to prepare.. Data: GDS-II Stream format Sample Resist
Cadence(VDEC standard, free of charge), L-Edit, etc.
Cadence is accesible at usr1.vdec.u-tokyo.ac.jp
Sample
We can buy jointly 4 inch and 5 inch wafers.
13,000円/4inch, 14,000円/5inch
Charged to the labo after consuming 10 masks.
Resist
In case of direct exposure.
ZEP-520A can be used as a common chemical.
Developer, etc
Chemicals for photomask is offered by VDEC
ZED-N50 and ZMD-B are common chemical. No Xylene.

5. Wafer spec. for direct exposure
Sensitive to thickness variation
Optical height detector (OHD) range is narrow: ±50µm
Exposure without OHD is possible in return to precision.
Surface height is the only restriction (mechanical methods)
Accepted Thickness range by OHD
Alternative: Electron Beam height adjustment
Pro: Thickness range: 0.2～1mm
Con:Detection mark obligatory on wafer (3mm×3mm)

6. 図形演算 hierachical schematics
Exposure Procedure１ y
１．GDS stream file
Cadence、L-Edit等 x
Center must be (0,0)
sftp and login usr1.vdec
Chip is center-center aligned.
Rectangle border
For nega-posi inversion. Layer number 255
２．GDS preprocessing 　　(bexelwin)
Nega-posi (subtract)
図形演算 hierachical schematics
Unetched on CAD figure
元GDS
Cut （and）
Toward the “2GB wall”：
Partial conversion is possible
Mirroring
gdsmodify
If you want you figure non-mirrored on photomask
３．BEFフォーマット変換(bexelwin)

7. （３．５）Shot correction (depreciated)
Exposure Procedure ２
２．GDSファイル前処理
３．BEF conversion (bexelwin)
Main Field: 1.6mm×0.8mm
Sub Field:80μm□
BEF読込GDStoBEF
Format conversion
Field segmentation
（３．５）Shot correction (depreciated)
GDS
raw BEF
４．BEF shot decomposition (bexelwin)
BEF読込decomposition
sftp and login eb3.vdec
raw BEF
exposure-ready BEF
ftp to “w”
Remember to cleanup directory by “rm” command
Enter Cleanroom
５．日常点検(uTile)

8. Exposure Procedure ３ ５．Daily check(uTile) ６．Set sample
クリーンルーム入室
Auto calibration
５．Daily check(uTile)
First user of day：execure 「日毎」（３０min）
Last user on Friday： execute 「週毎」（１h）
300,000yens after discount。
６．Set sample
Put sample on the “Adjuster”
Make sample conductive by groundpin or Cu tape
Install adjuster in the machine, declare adjuster by command “vdec” on the workstation “c”
Exec “vdec” on WS “c”
Work on “w”
Sample
Adjuster
７．BEF reading(uTile)
Workstation “w”. Read BEF file into uTile program.
Attention to the “wall of 2GB”
８．WECの作成１：高さ計測定チップ指定(uTile)

9. （１０）Set 「調整」 for alignment exp.
Exposure Procedure ４
７．BEFの登録(uTile)
８．WEC creation１：OHD meas. Chip set (uTile)
Each place is called “chip”.
For focus automatic correction.
Number of chips: ９～２５chips. Over 9 preferred.
９．WEC creation ２： 　Placement　(uTile)
Read BEF in a group, place, and define dose.
Chip pitch, placement, offcet definition
In each group maximum 4 designs
Offset is useful
（１０）Set 「調整」 for alignment exp.
１１．Batch creation ：(uTile)
Read WEC
Set batch number “1”
１２．配置確認 (W号機、Wad.sh)

10. Exposure Procedure ５ １２．Placement verification (W号機、wad.sh)
１１．バッチの作成：(uTile)
１２．Placement verification (W号機、wad.sh)
Verification is possible
Out of guarantee of Advantest
１３．Adjuster set　(WS “c”)
Execute command 「vdec」 on workstation “c”, to be sure.
Login “c”? ：On “w”, exec →端末エミュレーター→「rlogin c -l dax5」
１４．Exposure
バッチ選択→「露光開始」 for exposure.
バッチ選択→ウェハ搬送「ロード」→単枚露光→「アンロード」 is possible.
１５．Development

11. WEB reservation http://www.vdec.u-tokyo.ac.jp/
Click
公開装置利用予約
30 minutes slot (with 30min of margin)
One mask takes around 2 hours including all.

12. Administrative things
Reservation: 「公開装置予約」
Necessary: VDEC WEB
Wiki page is under construction on eb3.vdec.u-tokyo.ac.jp, accesible from cleanroom and eb3 itself
Make condition common knowledge
Learn altogether how to use calculator, what to calculate is your originarity.