1 of 8

Blu-Ray Lithography

Introduction

This is the project page for a lithography system based on repurposing Blu-Ray drives. The initial goal is to reach a feature size of at least 500nm (2x the Blu-ray laser spot size). As a stretch goal, we would like to also use the sled and spindle motors as high speed nano-positioners and to spin coat and cure photo-resin.

Project Status

Right now, the first project for this technology (Lithography Spinner V1) is in the research/idea stage. See work in progress page for details on upcoming tasks if you want to contribute.

Work in Progress

Planning

In-Progress

Done

KEM-497AAA Pin Out Analysis

Want to work on something? Plan a task add your name next to it!

KEM-497AAA Pin Out Analysis

TBD

Lithography Spinner V1

Introduction

The Lithography Spinner V1 plans to use the Blu-Ray disc assembly from a Play Station 5 (KEM-497AAA) to drive the whole system. They are readily available and can be found for $30-$70 in most places.

Typically a single IC is used to drive these modules but most vendors wont sell chips to individuals. So the plan is to design a discrete controller board to manage all the HW and write our own controller SW.

Documentation

Project Specification

Datasheets

Design Datasheets

Motor controller and Red/IR LED Driver https://www.ti.com/lit/ds/symlink/tpic2050.pdf?ts=1739885334186&ref_url=https%253A%252F%252Fwww.google.com%252F
LVDS Serializer https://www.ti.com/lit/ds/symlink/sn65lv1023a.pdf?ts=1740059186342&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FSN65LV1023A

Reference Datasheets

ToF Laser diode driver https://www.infineon.com/dgdl/Infineon-IRS9102C-DataSheet-v01_00-EN.pdf?fileId=8ac78c8c919c9f9d01923335dc1b43c5
Blu-Ray Laser Diode Driver https://www.renesas.com/en/document/sds/isl58797-data-short?r=506001 https://www.renesas.com/en/document/dst/isl58792-datasheet https://rocelec.widen.net/view/pdf/eyrlshzeil/ATMLS04748-1.pdf?t.download=true&u=5oefqw
Blu-Ray Laser Diode https://media.digikey.com/pdf/Data%20Sheets/Sharp%20PDFs/GH04P21A2GE.pdf
Photo Detector IC https://www.digchip.com/datasheets/download_datasheet.php?id=3143605&part-number=MLX75012
CMOS to LVDS Driver https://www.analog.com/en/products/adn4661.html

Hardware

Software

Introduction

The SW needed for this project can be broken down into the following subsections.

Pattern Capture

KLayout

OpenROAD

CAM Translator

Computer-Aided Manufacturing software translates a 3D design into G-code instructions that a CNC machine (in this case laser burner) can understand, essentially "slicing" the design into smaller, machinable steps.

This SW takes a file with the desired mask (Pattern Capture Output) as an input and translates it into a set of machine instructions.

Burner Firmware

This software runs on the micro-controller that drives all the HW. It is responsible for taking sensor inputs and driving all output motors and lasers. This device also has an interface which can transmit all the data to/from the user.

Device Driver

This software is responsible for general control of the laser burner from the PC side.

Graphical User Interface

This SW is responsible for the user facing interface which gives the user full control of the burner.

Base Principles

This page contains topics that are good to know if you want to contribute to this project.

Optical

Minimum Spot Size (Rayleigh Criterion)

The Rayleigh criterion is a measure of the limit at which two points of light can be distinguished as separate. It states that two points are resolvable when the principal diffraction maximum of one image coincides with the first minimum of the other. In simpler terms, it defines the smallest angular separation at which two light sources appear distinctly separate rather than as a single blurred point. This criterion helps in understanding the resolving power of optical instruments. When the Rayleigh criterion is expressed in terms of the numerical aperture, the equation becomes:

$d =\frac{0.61λ }{NA}$

where:

d is the minimum resolvable spot size,
λ\lambda is the wavelength of light,
NA is the numerical aperture of the lens.

For blu-ray the wavelength is 405nm and the NA is 0.85 resulting in a spot size of 290nm.

Source/Reference

Video explanation of resolution in optics (relevant info starts at 27:15 but the entire video is a great introduction to optics) https://www.youtube.com/watch?v=sTa-Hn_eisw

Minimum Feature Size

The minimum feature size in transistors, often referred to as the "technology node" or "process node," represents the smallest dimension of a transistor on a semiconductor chip. This size is measured in nanometers (nm) and dictates how densely transistors can be packed on a chip, which in turn influences the chip's performance, power consumption, and overall size.

Transistor sizes through the years (needs to be corrected)

Year

Node Process

Width (nm)

Length (nm)

1968

20,000 nm

100 nm

20,000 nm

1971

10,000 nm

100 nm

10,000 nm

1974

6,000 nm

100 nm

6,000 nm

1977

3,000 nm

100 nm

3,000 nm

1981

1,500 nm

100 nm

1,500 nm

1984

1,000 nm

100 nm

1,000 nm

1987

800 nm

100 nm

800 nm

1990

600 nm

100 nm

600 nm

1993

350 nm

100 nm

350 nm

1996

250 nm

100 nm

250 nm

1999

180 nm

100 nm

180 nm

2001

130 nm

100 nm

130 nm

2003

90 nm

100 nm

90 nm

2005

65 nm

100 nm

65 nm

2007

45 nm

100 nm

45 nm

2009

32 nm

100 nm

32 nm

2010

28 nm

100 nm

28 nm

2012

22 nm

100 nm

22 nm

2014

14 nm

100 nm

14 nm

2016

10 nm

100 nm

10 nm

2018

7 nm

100 nm

7 nm

2020

5 nm

100 nm

5 nm

2022

3 nm

100 nm

3 nm

OPU Architecture

Note: It is recommended to keep the cover layer, whose thickness depends on the operation wavelength, in front of the OPU objective lens to guarantee optimal laser focusing. Microscopy cover glasses provide a similar refractive index (1.47 to 1.5) as the cover layer or one can simply use the disc hard-coat polycarbonate cover layer. Furthermore, the cover layer can be used for sealing microfluidic channels. OPU-based imaging or sensing through different media, such as liquid or gas, demands the optimization of the distance between the cover layer and measurement target

Source

https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/

Photo-diode Auto-focus

Optical pickups focus on disc using the so called astigmatic method. This method is based on the deformation of the roundness of the laser beam when it is unfocused. The pickup has a series of lenses that lead the reflected ray to a photodiode array which generates four signals (A,B,C,D). Using them it is possible to deduct if the laser is unfocused and move the lens to focus it correctly.

Once you know the A,B,C,D signal pins, implementing the auto-focus algorithm is easy: just add A+C and subtract B+D from the result. The pickup returns those signals in the form of minimum current variations that depend on the laser light received by each photodiode. The photodiodes are arranged in a square (see following figure).

As you can see, it is possible to infer the focus level checking if the result is less than 0 (too close) equal to zero (focused) or greater than zero (too far) and with this information move the lens until the laser is focused.

Sources

http://www.diyouware.com/node/161 https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/

Mechanical

Mechanical Resolution - Step size

The minimum needed step size can be determined by the perimeter of the writing area and the minimum spot size

For the largest radius (58mm) the perimeter is 364mm
For the smallest radius (23mm) the perimeter is 144mm

From there number of steps is calculated by:

Assuming a 290nm spot size:

For the largest radius (58mm) the number of steps is 1.256M
For the smallest radius (23mm) the number of steps is 498k

Mechanical Resolution - Repeatability

The planned approach for repeatability is closed loop control. Since the blu-ray system works on reading concentric circles each disc will have a pattern written along the ring perimeter that identifies what is the current ring radius. It will also be used to help identify the start position on the perimeter.

Maximum Wafer Size

Since this project plans to use a blu-ray drive, the working area is basically the entire readable area of a disc (including table of contents).

The start of the writing area for a disc is 46mm in diameter or 23mm in radius.
The end of the writing area for a disc is 116mm in diameter or 58mm in radius.

Therefore the writing radius is about 35mm.

Maximum Symmetrical Die

5x Symmetrical dies can fit on a disc assuming 30mm x 30mm (900mm^2)

Maximum Asymmetrical Die

4x Asymmetrical dies can fit on a disc assuming 25mm x 50mm ( 1,250mm^2 )

Disc Revolution Speed

To calculate how fast the disc needs to spin we first need to know how fast the spot we need to image is moving. the speed is dependent on how far we are from the center of the disc.

If we assume a random rotational speed in revolutions per minute (rpm), we can use the following steps to calculate how fast the imaging spot is moving:

Convert rpm to revolutions per nano-second (rpns):

Calculate the linear speed in nano-meters per nano-second (nm/ns):

Assuming the disc is spinning at 500rpm:

The smallest inner radius of the disc (23mm) is moving at roughly 1.24nm/ns
The largest outer radius of the disc (58mm) is moving at roughly 3.03nm/ns

Material

Positive and Negative Photo-resist (TBD)

Minimum Developed Spot Size (TBD)

Relevant Works

Blu-Ray Specifications

Laser Scanning Microscope (Doctor Volt)

This is a 3 part video series where Doctor Volt dissects a Blu-ray player to figure out how to make a laser scanning microscope out of it.

PT1. Blu-Ray laser tear-down

https://www.youtube.com/watch?v=liGuhbFh4IQ

PT2. Mechanical Assembly

https://www.youtube.com/watch?v=Hkialty_8K4&t=267s

PT3. SW and Resolution Improvements

https://www.youtube.com/watch?v=xfuWbnMYOos&t=72s

DVD Laser Assembly Tear-down (tsbrownie)

Functional walk through of laser head assembly

https://www.youtube.com/watch?v=-7IRB7lb9lQ

Edwin Hwu's Research Hacking Blu-Ray

Hacking Blu-ray for High-Resolution 3D printing

https://backend.orbit.dtu.dk/ws/files/239879723/SSDM2020_Abstract_Edwin.pdf

Hacking Blu-ray for High-Throughput 3D printing

#Paper

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11677/116770A/Hacking-blu-ray-drives-for-high-throughput-3D-printing/10.1117/12.2576491.short

#Video

https://www.youtube.com/watch?v=Fw8r5FBaPTI&t=1281s

Hacking CD/DVD/Blu-ray Optical Pickup Unit (OPU) for Fun and Scientific Research

https://www.youtube.com/watch?v=5bqujaldaCQ

Hacking CD/DVD/Blu-ray for Biosensing

https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/

Tear-down of PHR-803T Laser Module (diyouware)

Future Improvements

STED Lithography (reaching 100nm and below)

STED Microscopy https://www.youtube.com/watch?v=1pgpzHao1c0
Two-beam OBL utilizes a doughnut-shaped inhibition beam to inhibit the photopolymerization triggered by the writing beam at the doughnut ring leading to reduced feature size and improved resolution https://www.nature.com/articles/ncomms3061
Super-resolved critical dimensions in far-field I-line photolithography https://www.spiedigitallibrary.org/journals/journal-of-micro-nanolithography-mems-and-moems/volume-18/issue-1/013505/Super-resolved-critical-dimensions-in-far-field-I-line-photolithography/10.1117/1.JMM.18.1.013505.short

Base Principles

This page contains topics that are good to know if you want to contribute to this project.

Optical

Minimum Spot Size (Rayleigh Criterion)

$d =\frac{0.61λ }{NA}$

where:

d is the minimum resolvable spot size,
λ\lambda is the wavelength of light,
NA is the numerical aperture of the lens.

For blu-ray the wavelength is 405nm and the NA is 0.85 resulting in a spot size of 290nm.

Source/Reference

Video explanation of resolution in optics (relevant info starts at 27:15 but the entire video is a great introduction to optics) https://www.youtube.com/watch?v=sTa-Hn_eisw

Minimum Feature Size

Transistor sizes through the years (needs to be corrected)

Year

Node Process

Width (nm)

Length (nm)

1968

20,000 nm

100 nm

20,000 nm

1971

10,000 nm

100 nm

10,000 nm

1974

6,000 nm

100 nm

6,000 nm

1977

3,000 nm

100 nm

3,000 nm

1981

1,500 nm

100 nm

1,500 nm

1984

1,000 nm

100 nm

1,000 nm

1987

800 nm

100 nm

800 nm

1990

600 nm

100 nm

600 nm

1993

350 nm

100 nm

350 nm

1996

250 nm

100 nm

250 nm

1999

180 nm

100 nm

180 nm

2001

130 nm

100 nm

130 nm

2003

90 nm

100 nm

90 nm

2005

65 nm

100 nm

65 nm

2007

45 nm

100 nm

45 nm

2009

32 nm

100 nm

32 nm

2010

28 nm

100 nm

28 nm

2012

22 nm

100 nm

22 nm

2014

14 nm

100 nm

14 nm

2016

10 nm

100 nm

10 nm

2018

7 nm

100 nm

7 nm

2020

5 nm

100 nm

5 nm

2022

3 nm

100 nm

3 nm

OPU Architecture

Source

https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/

Photo-diode Auto-focus

Sources

http://www.diyouware.com/node/161 https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/

Mechanical

Mechanical Resolution - Step size

The minimum needed step size can be determined by the perimeter of the writing area and the minimum spot size

$perimeter ={2 * π * radius}$

For the largest radius (58mm) the perimeter is 364mm
For the smallest radius (23mm) the perimeter is 144mm

From there number of steps is calculated by:

$steps = \frac {perimeter}{min spot size}$

Assuming a 290nm spot size:

For the largest radius (58mm) the number of steps is 1.256M
For the smallest radius (23mm) the number of steps is 498k

Mechanical Resolution - Repeatability

Maximum Wafer Size

Since this project plans to use a blu-ray drive, the working area is basically the entire readable area of a disc (including table of contents).

The start of the writing area for a disc is 46mm in diameter or 23mm in radius.
The end of the writing area for a disc is 116mm in diameter or 58mm in radius.

Therefore the writing radius is about 35mm.

Maximum Symmetrical Die

5x Symmetrical dies can fit on a disc assuming 30mm x 30mm (900mm^2)

Maximum Asymmetrical Die

4x Asymmetrical dies can fit on a disc assuming 25mm x 50mm ( 1,250mm^2 )

Disc Revolution Speed

To calculate how fast the disc needs to spin we first need to know how fast the spot we need to image is moving. the speed is dependent on how far we are from the center of the disc.

If we assume a random rotational speed in revolutions per minute (rpm), we can use the following steps to calculate how fast the imaging spot is moving:

Convert rpm to revolutions per nano-second (rpns):

$rpns =\frac{rpm }{60*10^{9}}$

Calculate the linear speed in nano-meters per nano-second (nm/ns):

$Linear speed (nm/ns)=radius (nm)×2×π×rpns$

Assuming the disc is spinning at 500rpm:

The smallest inner radius of the disc (23mm) is moving at roughly 1.24nm/ns
The largest outer radius of the disc (58mm) is moving at roughly 3.03nm/ns

Material

Positive and Negative Photo-resist (TBD)

Minimum Developed Spot Size (TBD)

Relevant Works

Blu-Ray Specifications

White Paper Blu-ray Disc Format General

http://educypedia.karadimov.info/library/general_bluraydiscformat-15263.pdf

White Paper Blu-ray Disc Format BD-R

https://blog.ligos.net/images/The-Reliability-Of-Optical-Disks/BD-R_physical_specifications-18326.pdf

White Paper Blu-ray Disc Format BD-RE

https://blog.ligos.net/images/The-Reliability-Of-Optical-Disks/White_Paper_BD-RE_5th_20180216.pdf

Laser Scanning Microscope (Doctor Volt)

This is a 3 part video series where Doctor Volt dissects a Blu-ray player to figure out how to make a laser scanning microscope out of it.

PT1. Blu-Ray laser tear-down

https://www.youtube.com/watch?v=liGuhbFh4IQ

PT2. Mechanical Assembly

https://www.youtube.com/watch?v=Hkialty_8K4&t=267s

PT3. SW and Resolution Improvements

https://www.youtube.com/watch?v=xfuWbnMYOos&t=72s

DVD Laser Assembly Tear-down (tsbrownie)

Functional walk through of laser head assembly

https://www.youtube.com/watch?v=-7IRB7lb9lQ

Edwin Hwu's Research Hacking Blu-Ray

Hacking Blu-ray for High-Resolution 3D printing

https://backend.orbit.dtu.dk/ws/files/239879723/SSDM2020_Abstract_Edwin.pdf

Hacking Blu-ray for High-Throughput 3D printing

#Paper

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11677/116770A/Hacking-blu-ray-drives-for-high-throughput-3D-printing/10.1117/12.2576491.short

#Video

https://www.youtube.com/watch?v=Fw8r5FBaPTI&t=1281s

Hacking CD/DVD/Blu-ray Optical Pickup Unit (OPU) for Fun and Scientific Research

https://www.youtube.com/watch?v=5bqujaldaCQ

Hacking CD/DVD/Blu-ray for Biosensing

https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/

Tear-down of PHR-803T Laser Module (diyouware)

Future Improvements

STED Lithography (reaching 100nm and below)

STED Microscopy https://www.youtube.com/watch?v=1pgpzHao1c0
Two-beam OBL utilizes a doughnut-shaped inhibition beam to inhibit the photopolymerization triggered by the writing beam at the doughnut ring leading to reduced feature size and improved resolution https://www.nature.com/articles/ncomms3061
Super-resolved critical dimensions in far-field I-line photolithography https://www.spiedigitallibrary.org/journals/journal-of-micro-nanolithography-mems-and-moems/volume-18/issue-1/013505/Super-resolved-critical-dimensions-in-far-field-I-line-photolithography/10.1117/1.JMM.18.1.013505.short
Possible STED Architecture Diagram of BSM. The fluorescence signal passes through multimode fiber B7 and is collimated by collimator lens B8 and narrowband emission filter B9. D1, laser diode; D2, beam splitter; D3, collimator lens; D4, dichroic filter; D5, photodiode; D6, objective lens (NA: 0.6); D7, Al-coated address pattern; B1, blue laser diode; B2, B3, beam splitters; B4, collimator lens; B5, dichroic filter; B6, 4.34 mm focal lens; B10, objective lens (NA: 0.85); B11, lens holder. B12, cover glass; B13, collimator astigmatic plate; B14, photodetector. (https://pmc.ncbi.nlm.nih.gov/articles/PMC6066758/)