Tool Selection Procedure in CNS

-Is it possible to make everybody happy?

Jiangdong Deng (JD), Ph.D

Manager of Nanofabrication Facility

Center for Nanoscale Systems (CNS)

Harvard University

OUTLINE

l CNS Operation and Nanofabrication Capability

l Tool Acquisition Approaches in CNS

l Major capital equipment acquisition procedure in CNS

l Tool acquisition example- Deep Oxide RIE

l Summary -benefit discussion

Harvard Other UniversitySmall Company Large Corporation4-year college 2-year collegeIntl. Instit. or Corp.

Center for Nanoscale Systems:Harvard University

The Mission at CNS:Evolve and nurture one of the mostcomprehensive nanotechnology researchcommunities in the world. Supporting thedevelopment of new materials and devices.

Nanofabrication•Component driven•Complete lithography tool set

•Non-traditional materials

Electron Microscopy/Analysis•Advanced Tools•Core expertise in CryoTEM

•Atom Probe tomography

LABORATORY FOR INTEGRATED SCIENCEAND ENGINEERING (LISE):

10000 ft2 Cleanroom

6000 ft2 Hi-resolution EM Imaging Suites

3000 ft2 Cell Culture Lab

Soft lithography/BioMaterials Lab

Optical Spectroscopy Lab

Scanning Probe Microscopy Lab

• >1600 current users • >160,000 hours of use• >28 fulltime Staff• Multidisciplinary userbase

CNS User Types FY15:

“Enabling Next Generation Nanoscience”

Materials

Life Science

Physics

Optics and Photonics

Chemistry

ElectronicsMEMS

OtherMechanics

MedicineEducational

LabsGeology

and Earth Science

Process Technology

CNS User disciplines FY15:

CNS Lithography Capabilities

1nm 10mm1mm100nm10nm 1um 100um10um

SLF-4 printer0.1-10mm

UV Flood Exposure0.1-10mm

Nanoscribe -3D lithography >150nm @x,y>200nm @z

AutoStep 200 i-line stepper

EBL-ELS-F125> 5 nm

EBL-Raith150 >20 nm

EBL-ELS7000> 7 nm

EBL-Jeol-7000 > 30 nm

MW-3 uPG501> 1 um

MW-1 Mask Writer > 0.6 um

Heidelberg MLA system >1um

AB-M aligner> 2 um

OL-4 MJB4>1 um

MA6 Mask-Aligner> 0.7 um

MJB-3 aligner>2 um

EVG620 Mask aligner >1um

5

Reactive Ion Etching (RIE) Capability

RIE Capability in CNS

Si Diamond III-V Oxide (SiO2, LiNbO3, ZnO2,

Al2O3..

Metal Polymer Strippers

SPM and Nanoscale Spectroscopy

Veeco NanoMan (6 in stage) M-Vista PiFM

Building up the facility of CNS

l Center founded and initial stage: 1999-2005, foundation building ~2000 up to 3500 ft2 CR space +2000 ft2 Imaging lab (in 4 labs) old tools inherited, plus first equipment fund (~$ 8 M) Basic tool set: Raith 150 EBL, Heidelberg DWL-66, MA6, metrology, NEXX RIE and PECVD, Unix

RIE, PVD, LPCVD (single wafer), Jeol TEM, SEMs,

l Developing stage, 2005-2010, New facility lab- LISE building $150M, $20M equipment , nanofab (33%), Imaging (44%), and material (23%) Elionix-7000, STS RIE and PECVD, Sputtering, ALD, LPCVD, SPMs, cs-TEMs, SEMS, FIBs,

l Advancing stage, 2010-2015, **large user pool (1600) and diverse research demanding** Managing large user community (training, maintenance, safety control,

process development) Continue filling up the technical gap New capability expansion for new research needs Process baseline establishing and enhancement User research involvement

CNS Tool Acquisition Channels

Approach 1: Faculty’s equipment funding (like start-up package)

Approach 2: Instrument grant from NSF-MRI, NIH, DURIP…

Approach 3: Industry donation, auction, sale…

Approach 4: Home made equipment (ALD, XeF2…)

Approach 5: System loaned by company (profiler, Heidelberg, Asylum AFM, He-ion Microscope, Hitachi AFM, Hitachi CD-SEM >6months ***)

Approach 6: Capital equipment budget (~$ 2M/year since 2012)

• Old tool replacement or upgrade

• New technology to meet new research needs

Bridging Research Needs and Available Technology

CNS Tool Evaluation Team (staff, major user groups)

Top management

Vendor candidates ABC:

Research needs from user site:

Group 1Group 2Group 3

:

Evaluation report

New tool acquisition and commissioning procedure in CNS

Proposal and Justification

• Initial Requirement from Users site

• Searching tool candidates (2-4): • Workshop and quotation

• User feedback (2-3 key faculties)

• Justification and Budget approval

Evaluation

• Evaluation team forming • key faculties, users, staff

• Sample preparation for demo• specification defining (based on

needs!!!)• sample fabrication (user, and CNS

staff)• Vendor DEMO process to meet the

spec. • discussion between evaluation

group and vendor, • demo report from vendors

• Reference checking • Process DEMO results summarize

and report • Committee review and decision

Commissioning

• PO processing• Tool assembling • FAT• Tool shipment and hookup • Hardware acceptance• Process acceptance to repeat

sample DEMO results• Training document

preparation• Baseline process set up• Open to the user

New tool acquisition and commissioning procedure in CNS

Proposal and Justification

• Initial Requirement from User site • Searching tool candidates (2-4):

• Workshop and quotation• User feedback (2-3 key faculties)• Justification and Budget approval

New tool acquisition and commissioning procedure in CNS

Evaluation

• Evaluation team forming • key faculties, users, staff

• Sample preparation for demo• specification defining (based on needs!!!)• sample fabrication (user, and CNS staff)

• Vendor DEMO process to meet the spec. • discussion between evaluation group and vendor, • demo report from vendors

• Reference checking • Process DEMO results summarize and report • Committee review and decision

New tool acquisition and commissioning procedure in CNS

Commissioning

• PO processing• Tool assembling • FAT• Tool shipment and facilitation • Hardware acceptance• Process acceptance to meet the spec.• Training document preparation• Process baseline set up• Open to the user

Tool Acquisition Example- Deep Oxide RIE

l Deep Oxide RIE Request from CNS-Nanofabricationl Evaluation Team l RIE Manufacturer Candidate and Hardware configuration

2-4 Vendors/systems (A, B, C,D)

l Process DEMO Specs and Results DEMO#1, High aspect ratio 100nm SiO2 trench etch (from

Evelyn’s group) DEMO#2, Sub-um SiO2 pillar etch (from HK Park) DEMO#3, LiNbO3 waveguide etch (from Loncar)

l Reference Checkl Evaluation Report for Committee Review

Deep Oxide RIE Purchase Justification

• Take over SiO2/Si3N4 etchings from STS RIE The STS RIE is the busiest etching tool in the cleanroom, its monthly usage is ~300 hours from 261

users, even higher than that of Unaxis (169 users, ~250 hrs/month). The STS RIE has been used for etching Si and SiO2/Si3N4 since its installation, which made the Si etch

rate fluctuated remarkably due to the interferences between etching processes. Users have to test the etch rate before every etching, which is very time consuming.

More frequent chamber cleans are required to keep the Si etch rate within a reasonable range. Major user groups: Hongkun Park, Charles Lieber, Rowland Institute, Wyss Institute , Amir Yacoby,

Marko Loncar, Evelyn Hu, several groups from MIT and other institutes of New England.

• Expand Etch Capability Several groups require deep oxide etchings, 2 microns or deeper with an aspect ratio greater than 5.

None of CNS existing RIEs are able to meet the needs. These groups include Hongkun Park (nanowire array), Evelyn Hu, Joanna Aizenberg (nano pillars), Wyss Institute (Microfluidic device), and MIT (photonics).

Open the etching capability to SiC, ZnO, ZrO2, Al2O3 materials, which is essential for some LED, sensor groups.

• Replace Nexx RIE Nexx RIE is aged, ~16 years old. This tool is used to etch all materials including except III-V, including Si,

SiO2, and Si3N4, metals, other oxides, and polymers. Two big issues exists on this tool: i) down frequently; ii) low etching repeatability. Both issues are

caused by the poor designs of the chuck assembly and the wafer transfer unit. Users have been frustrated by the above issues. Major user groups: Eric Mazur, Marko Loncar, Evelyn Hu, Amir Yacoby, MIT and other institutes of New

England.

Evaluation Team: • CNS staff:

Kenlin Huang (RIE process engineer), S. Paolini(Equip. Eng.), Yuan/GX Zhong (Photo. Eng.), M. Tse, Ed Macomber (CVD eng.),Jiangdong (JD) Deng

• Research groups: - Alex Zhang, Evelyn Hu;- Tianyang Ye, H.K. Park; - Cheng Wang, Marko Loncar

Evaluation Time Period: July 2015- March 2016

Tool Acquisition Example- Deep Oxide RIE

DEMO #1, High aspect ratio 100nm SiO2 trench (from Evelyn’s group)

6 inch Si wafer / 3 um oxide / 150 nm Al / Patterned E-beam resist thickness 400 nm

Specificationl Trenches with CD / pitch: 50 nm / 300 nm, 100 nm / 500 nm, 250 nm / 600 nm,

1 um / 2 um.l Process Requirements:l 1. Etch profile : 90 +/- 2 degree. ( priority 1 )l 2. Sidewall roughness < 20 nm. ( priority 1)l 3. SiO2 : Al selectivity > 15 : 1 ( priority 2 )l 4. CD bias < +/- 5 % ( priority 3 )l 5. Etch uniformity < +/- 5% ( priority 4 )l 6. SiO2 etch rate > 100 nm /min ( priority 5 )l 7. Target at trenches with CD 100 nm, etch depth > 1 um, the deeper the

better. ( priority 1 )

Evaluation Report, Committee Review, and Decision Making

l Vendor A’s etching showed better profile control than A, B.

l Vendor A offered better price advantage than C.l Vendor A’s process support is more convenientl Vendor A has good user comments on service support.

l After final evaluation report reviewing, Vendor A- RIE was selected by the faculty committee,

l Results were also informed to other vendors.

Why this ‘complicated’ and long process for tool evaluation ?

• Benefits to CNS, user, as well as vendor • Find the right tool, which can meet the real

research needs in CNS• Enhance the ‘bonding’ between CNS staff

and the faculty groups • Staff training. Team work, cooperation, skill

set polishing..• Solid connection and collaboration with the

vendors • Developed and established new recipes (>

10 nanofabrication processes) in CNS in a short periods

So, seems that everybody is happy!?

NO! it is impossible!

But, at least, it is acceptable, because of the open, transparent, and data-driven procedure!

New Tools at CNS (Nanofabrication) in FY16:Expanding capabilities for one of the most comprehensive nanotechnology research communities in the world.

Nanofabrication Additions (5/2015-7/2016):• Nanoscribe 3D lithography system (MRI) (July, 2015)• Heidelberg MLA-150 (loaner, June 2015)• Asylum Cypher ( July, 2015)• 100MHz high speed blanker for Ellionix –E125 (July, 2015)• Comsol nanofabrication Simulation software (Sep. 2015)• Cambridge Nanotech- ALD (used tool, Nov. 2015)• Phi-ALD (homebuilt, Oct. 2015) • Hitachi Environmental AFM (loaner, Sep. 2015)• Hitachi CD SEM (loaner (Jan,2016)• ULVAC deep Oxide RIE (June 2016)

Focus: to enhance tools needed by our core research programs adding resources, tools, and staff to support transformative science and

technology development.