This is a temporary solution to a long-term problem.
Get off the Rock
- The Artemis Project - The project is a private venture to establish a permanent, self-supporting community on the Moon. Brief overview of the Artemis project.
- The Mars Society - To further the goal of the exploration and settlement of the Red Planet.
- The Moon Society - An international nonprofit educational and scientific foundation formed to further the creation of communities on the Moon involving large-scale industrialization and private enterprise.
- National Space Society - grassroots organization dedicated to the creation of a spacefaring civilization. Magazine.
- Stanford on the Moon (by 2015?) And yes, Stanford as in the university.
- Space Frontier Foundation - seems to have projects for space colonization, missions to the Earth's moon, and so on. Looks like a large scale organization.
- The Space Settlement Initiative
- Space Access Society - activism for getting out of the NASA-only paradigm/reality.
- Students for the Exploration and Development of Space - `... is dedicated to expanding the role of human exploration and development of space. We also seek to educate the public in such a way as to attain this goal. `
- Space Studies Institute - `SSI’s stated mission is: Opening the energy and material resources of space for human benefit by completing the missing technological links to make possible the productive use of the abundant resources in space.`
- International Space University - `The International Space University provides graduate-level training to the future leaders of the emerging global space community at its Central Campus in Strasbourg, France, and at locations around the world. ` (mentions 'systems engineering' on the About page)
- Space Settlement Institute - `The Space Settlement Institute is a non-profit association founded to help promote the human colonization and settlement of outer space. `
- Cygo's Space Initiative - plan and conduct exploration missions to minor planets, build and mass produce (while in space) a multi-purpose interconnectable module, and to offer products and services using space and the materials therefrom.
- Freeluna - `Freeluna.com is dedicated to the proposition that the colonization of outer space is critical for the long term survival of the human species, and that colonization of the moon and the exploitation of the moon's natural resources is one of the very best first steps in that incredible journey off planet.` ... and when I first visited this page, I was visitor #3371. Yikes. Contact: Bill Clawson, wclawson@freeluna.com
- Island One Society - associated with the Artemis society, seems to be mostly a resource-help site.
---- special ones:
- The Living Universe Foundation - `The Living Universe Foundation seeks to bring the galaxy alive with life from Earth, while healing the damage that humanity has already inflicted upon the Earth. We believe that expansion into space in the immediate future is a step towards accomplishing this aim.` turmith@yahoo.com --- This organization was inspired by the publication of a certain book. This is heavily related to Project Atlantis or Oceania (artifical floating city out in the sea) which is now defunct.
- Foundation Future 25 - ` Future 25 will be dedicated to the long-term view, supporting the lasting creation of new habitats. For the flora and fauna on earth, for humanity in outer space.
Open spaces and new ideas are the `Lebensraum' for our thinking and important for the development of human society. Future 25 will therefore support utopian thinking in terms of possible alternative societies and new ways for humans to live together. ` `at present we are a small group of engaged citizens.` Contact gros05@itp.uni-frankfurt.de ... Seems to have something called a result-oriented discussion forum that strangely resembles the Objective Branch idea. `The foundation Future 25 will therefore support the search for improving our societies, the thinking about alternative way to organize our society; utopian thinking. `
----
- NASA, but certainly not activism.
American Lunar Society - for the study of the Earth's moon
Idea spaces
Article space
- Edge magazine
- Whole Earth magazine
- Slashdot.org - "stuff that matters"
Yet-to-try
- Journal of Microelectromechanical Systems (J.MEMS)
- Journal of Micromechanics and Microengineering
- IEEE Transactions of Electron Devices
- Journal of Vacuum Science and Technology, B: Microelectronics and Nanometer Structures: Processing, Measurement, and Phenomena
* also see some books.
Books to read
Tools
See Whole Earth. The Whole Earth projects used to be about gathering up information about the whereabouts of tools, as started by our good friend Bucky Fuller.
- Zeiss document, supposedly a good introduction to optical microscopy
- `The Atomic force microscope (AFM) is mainly used to measure the topography of a surface, such as the roughness.`
- `Ellipsometers are used to measure thin film thicknesses by their optical properties (refractive index and reflectivity/absorbance).`
- `The four-point probe technique can be used to measure the conductivity of thin films. For improved measurements micro four-point probes can be used. Capres.com has an application note about micro four-point probes.[1]`
- Scanning Electron Microscopy
- ... also, possibly look into 'vacuum systems', a topic related to microfabrication.
Towards higher education
- Looking for ...
- Interesting curricula / plans
- Cornell's double majoring, providing options like ECE&ChE and ChE&CS. The idea of pursuing an education in electrical engineering, computer engineering, and chemical engineering at the same time is intruiging to me.
Adventures in natural languages
- English - native speaker
- Spanish - although I took 3 classes (6 semesters), maybe another semester that I have forgotten, I still have much to improve upon in my comprehension and ability to speak Spanish.
- German
- Russian
- Arabic
- Hindi
- Chinese
Stuff to look into
- Biomedical software, hardware, tools
TODO: See if micromachinery (see here) is able to move eukaryotic cells (10 micrometers in diameter?). Looks like we are doing 62 nanometer technology already, so presumably we can move objects that have a diameter of 5 to 15 microns (eukaryotic cell on the average according to this).- Micromachinery sensory inputs
- Micromachinery/MEMS/Nanomachinery/NEMS transceiver technology
- I think anybody may be able to guess where this is going: networking microtechnology to local Internet access nodes. Utah arrays have been wired to 802.11g before.
- Microtechnology and micromechanical devices (as defined at the Wikipedia microtechnology article)
- MEMS - microelectromechanical systems - which crosses over with nanoelectromechanical systems (NEMS) [1-]
Basically, this is molecular nanotechnology, or molecular engineering of molecular electronics.
- Electro Discharge Machining (EDM) [1-]
- Finite element analysis[1-]
- Silicon
- Polymers - MEMS devices can be made from polymers by processes such as injection moulding, embossing or stereolithography, and are especially well suited to microfluidic applications such as disposable blood testing cartridges.
- Injection moulding [1-]
- Embossing [1-] or stereolithography [1-]
- Metals - commonly used metals in MEMS includes Gold, Nickel, Aluminum, Chromium, Titanium, Tungsten, platinum, and silver.
- MEMS processes
- Deposition process
It is important in MEMS processing to be able to deposit thin films of materials. Thin materials is defined here as a thickness from a few nanometers to about 100 micrometers. Commonly used deposition processes include ...
- Electroplating
- Sputtering
- Physical Vapour Deposition (PVD)
- Chemical Vapour Deposition (CVD)
- Photolithography [1-]
MEMS-oriented lithography is the transfer of a pattern to a photosensitive material by selective exposure to a radiation source such as light. A photosensitive material is a material that changes in its physical properties when exposed to a radiation source. By masking some of the radiation we can selectively expose a photosensitive material to radiation and the pattern of the radiation on the material is transferred to the material exposed as the properties of the exposed and unexposed regions differ of course. This exposed region can then be removed or treated providing a mask for the underlying substrate. Photolithography is typically used with metal deposition, wet and dry etching.
- Etching processes
- Wet etching: the material is dissolved when immersed in a chemical solution
- Dry etching: the material is sputtered or dissolved using reactive ions or a vapor phase etchant.
- DRIE etching
- etc ... see more of the same *.
- etc ... see more of the same *.
- `Microtechnology is often constructed using photolithography[1-]. Lightwaves are focused through a mask onto a surface. They solidify a chemical film. The soft, unexposed parts of the film are washed away. Then acid etches away the material not protected.`
- The Opensource Handbook of Microfabrication and Microtechnology[1!*] (Microwiki)
See also the wikibook on semiconductors [1-] and nanotechnology [1-].
- Read up on microfluidics
- Read some books.
- Get some sort of knowledge on microfabrication materials
- Semiconductor materials[1-]
- ioffe NSM data archives [1-] - "semiconductor materials, characteristics and properties." - "These electronic archive contains frequently needed information for the most important Semiconductor Materials."
- Silicon[1-]
- Silicon dioxide[1-]
- Silicon nitride[1-]
*
- Gold[1-]
- Aluminium[1-]
- Polymers[1-]
- Process (cite 5Aug02006) (see Microfabrication and batch processing techniques)
- Additive processes (material added to wafer)
- Oxidation
- CVD
- Electromechanical methods
- Electroplating[1,2]
- Electroless depositions, such as electroless nickel plating [1]
- Sputter[1] deposition, particularly thin film deposition [1]
- Electron Beam Evaporation Coating [1]
- Epitaxial [1] growth
- Metal Organic Vapor Phase Epitaxy (MOVPE)
- `Molecular beam epitaxy [1] using solid sources and Chemical beam epitaxy [1] using gasseuos sources.`
- `Atomic layer epitaxy [1] where only a few monolayers are deposited and bond to chemisorption sites on the surface.`
- Surface modification
- Self-assembled monolayers [1]
- `Hydrophobe [1] and Hydrophile [1] surface layers to control wetting[1].`
- Rapid thermal anneal (RTA) [1]
- Wet etching [1,2]
- Table of echants [1,2]
- `See also the two papers 'Etch Rates for Micromachining Processing' Part I and II in Journal of Microelectromechanical Systems by Kirt R. Wiliams et al.`
- Extensive table with etch rates [1]
- Quick notes on avoiding "capillary effects"
- Use dry/gas etching instead of wet
- Use critical point drying
- `Quickly take wet etchant into a water rinse bath for a thorough rinse and then quickly into an ethanol batch and then dry - the low surface tension of ethanol reduces capillary effects when drying.`
- Silicon KOH Etch
- KOH is potassium hydroxide [1-]
- `Potassium hydroxide (KOH) is an anisotropic wet etch that preferentially etches the 100 planes of Si and almost doesnt attack the 111 planes. This leads to a V shaped pyramidal holes in Si 100 from square openings in the etch mask, with side edges at a 54.7deg angle from the surface. The etch rate does not depend on As, P, Sb dopants, but too high B doping will reduce the etchrate in the 110 direction. The etchrate in the 100 and 110 direction can be varied by adding isopropanol to the solution.`
- Overall reaction: Si+2OH- + 4H2O -> Si(OH)2++ + 2H2 + 4OH-
- Recipe for a typical 30% KOH/Isopropanol etch solution:
- 70g KOH pellets dissolved in 190mL DI water (use heat and/or ulrtasound to dissolve quickly)
- Add 40mL Isopropanol
- The etch rate for should be about 1 micron/minute at 80C
- `KOH etch masks can be made from silicon nitride or silicon oxide (though SiO2 is slowly etched by KOH)`
- Silicon node etching and cleaning [1-]
- 'Review: The effect of alcohol additives on etching characteristics in KOH solutions' Sensors and Actuators A 101 (2002) 255–261 by Irena Zubel
- Silicon Oxide Etch (BOE, BHF, HF)
Note that hyrdofluoric acid (HF) [1-] is very dangerous. HF diffuses quicker than anything you can add to try and reduce the damage, so the key is to not get in touch with it in the first place. It attacks the calcium in your bones, nerves, and bloodvessels. This does not burn like other acids. Wear labcoats, eyeprotection, 6h gloves, and work in a closed fumehood.
- Fundamental reaction SiO2 + 6HF -> H2SiF6+ 2H2O
- HF is a highly corrosive and toxic solution of hydrogen fluoride [1-] in water[1-]
- Buffered Hydrofluoric Etch (BHF) [1-] or Buffered Oxide Etch (BOE) [1-] is a mixture of ammonium fluoride [1-] and hydrofluoric acid[1-] with a "more controlled etch rate of silicon oxide[1-]".
- Ammonium fluoride containing etches gives silicon surfaces with an atomically smoother surface than HF, ammonium fluoride solutions can also be used to make atomically flat surfaces. See Appl. Phys. Lett. vol 56 p. 656 1990 by Higashi.
- `An oxide etch is often used to remove the impurity containing native oxide layer of wafers before contamination sensitive processes. BOE has a more controllable oxide etch rate than HF (the pH is stablilized by the buffer) but also etches Si slowly and the higher pH in BOE can cause metal precipitation, so for clean processes or thin underlying Si layers a HF etch is preferable.`
- `49% HF is used for fast removal of oxide`
- `BOE gives a slower removal of oxide, but can extend the lifetime of a photoresist mask. Etch rate typically 1000-2500 Å/min.`
- `Diluted HF etches - say 5% HF - is used for removal of native oxide in about 30 seconds. The surface becomes highly hydrophobic.`
- `HF/HCl or HF/Glycerin mixtures can be used to make less rough surfaces when thinning oxide layers`
- `HF mixed with isopropanol can be used to increase the wetting properties of the solution to better etch into narrow pores.`
- `Etch rates vary depending on on oxide quality (eg. wether its wet furnace grown or PECVD)`
- Recipe for Bufferd Oxide Etch (BOE) or Buffered Hydrofluoric Etch (BHE)
- `Prepare the 40% NH4F solution, eg 40g NH4F in 60mL water.`
- `6 parts 40% NH4F and 1 part 49% HF - HF etches glass so use plastic beakers! Add HF into NH4F instead of NH4F into HF.`
- Recipe for BHF/HCL etch for smooth oxide
- `Add 5mL Buffered Oxide etch as above to 85mL water`
- `Add 10mL conc. HCL`
- (? is this in reference to the recipe for BHF/HCL etch for smooth oxide?*) `Etch rate about 1 micron/min at room temperature.`
- Silicon Nitride Etch
- `Standard etch in H3PO4 100Å/min at 180C, 55Å/min at 165C. Use a short BHF dip first to remove oxynitride layer.`
- 10% HF 5000 Å/min
- 1% HF 600 Å/min
- BHF (7:1) 5-20 Å/min
- Metal etches
- Cleaning methods
In general there are several standard cleaning procedures, some even using many dangerous and highly corrosive chemicals. It would be a wise decision to keep things clean in order to avoid cleaning. Using simple soap rinses before starting on more dangerous processes will "probably" increase the quality of the result.
- Rinsing
- To keep the wafers from drying out they can be submerged into water-baths.
- Flushing your wafers with a jet of water is also an option.
- Ultrasound
Ultrasound baths work by standing waves of high frequency sound that at the wave anti-nodes create so high pressure variations that water vapor bubbles form and implode during the sounds pressure cycle. The bubble implosion creates shock waves that knock any loose material off surfaces and also can initiate chemical reactions or cause pitting in soft materials and damage smaller MEMS structures.
- Soap; oridinary soap can be useful, especially with ultrasound techniques
- RCA
This is a standard wafer cleaning method developed by the RCA corporation. It is made from two baths.
- RCA1 is a H2O:NH4OH:H202 cleaning of organic residues
- RCA2 is a H2O:HCL:H2O2 etch of metal impurities
Note that RCA cleaning is often used before "furnace processes". See also [1-].
- Piranha (no, not piranhas- .. although ...)
- Piranha solutions[1-] are often made from sulfuric acid (H2SO4) and hydrogen peroxide (H2O2). But basic solutions and other recipes are also named piranha. The solution is very corrosive. Use fumehood, labcoat, eyeprotection and nitrile/6H gloves. To show people have dangerous it is, try putting a small droplet on a piece of paper and see how it instantly is burned black.
- Acid piranha (Caro's acid, Sulfuric peroxide) - for 10mL Piranha, using glass beakers, pour 7mL 95% H2SO4 into 3mL 30% H2O2. The mixture heats on mixing to about 80C.
- Peroxydisulfuric etch (also nicknamed 7-up since it bubbles upon heating to 80C)
`This is a piranha etch with Ammoniumperoxydisulfate. Mix 1L 95% H2SO4 at 80C with a table spoon of Ammoniumpersulfate. The solution will start to bubble indiacting that it is ready. It can be reused several times until it does not bubble.`
- `Base Piranha is a 3:1 mixture of ammonium hydroxide (NH4OH) with hydrogen peroxide.`
`Piranha solutions etches organic compunds vigorously. It can form explosive compounds if mixed with organic solvents, so be careful and do not work near eg. acetone, ethanol or isopropanol with piranha.`
- `The exothermic heat of mixing can bring solution temperatures up to 120°C and can lead to violent boiling, or even splashing of the extremely acidic solution. Explosions may occur if the peroxide solution concentration is more than 50%. A 30% peroxide in water solution is more reasonable.`
- `Too thick organic contamination can harden up in piranha, so a degrease clean is often made before piranha cleaning.`
- `For instance a sequential cleaning as follows is often used for substrates used for epitaxial growth:`
- 2min sonication in Tri-chlor ethylene
- 2min sonication in acetone
- 2min sonication in ethanol
- 2min sonication in millipore water (MPW)
- then rinse in MPW 3 times.
- Piranha etch 6 min.
- Rinse in MPW 3 times.
- Dehydration brake 200-250C for 30 min.
- Dry etching [1-]
- Reactive ion etching (RIE) [1-]
- Advanced Silicon Etching (ASE) / Deep Reactive Ion Etch (DRIE) [1-]
- Plasma ashing [1-]
- Ozone cleaning [1-]
- Sputtering [1-]
- Gas etching
- `Hydro fluoric gas etching of oxide to avoid collapse of MEMS structures that would happen during drying if etched in aqueous fluoride etchants. See eg. [1-]`
- Lithography
- Ultra Violet Lithography (UVL)
- Photolithography [1-]
- Photoresist [1-]
- Masks for UVL
- Electron Beam Lithography (EBL) [1-]
- Determining the EBL resolution
- Beam diameter
- Resist sensitivity
- Development method ..
- Proximity effect[1-]
- Electron beam resists
- Resist coatings
- Spinning
- Electrochemical coating
- Spray coating
- Drop casting
- Self assembled monolayers
- Doping
- Implantation
- Spin-on doping
- Packaging
- Bonding
- Encapsulation
- Glues
- `Epo-tek H77 is a common packaging two-component UHV compatible epoxy glue.`
- `[Fortafix.com Fortafix] makes a high temperature glue that should work up to around 1000 C called Rocksett.`
Nanotechnology
Unsorted
- (August 5th, 02006): It has come to my attention that linking to Amazon.com books is a really, really stupid idea. First of all, there is some hate speech on the block for Amazon, and another problem is that they use an incredibly unknown URL scheme .. an alternative solution would be a database of books that would link to websites that stock that book. A web user could configure the website to automatically redirect to the Amazon website, or the Barnes&Noble website, et cetera; however, preferabbly, the URL will not look like some nasty TinyURL that's not-so-tiny. If this interests you too, please contact me.*
- (August 5th, 02006): A person's education could likely be centered around the periodic table of chemical elements. This education would include chemistry but also where the chemicals are, who controls these sources, the cycles of each atom, how they interact with each other, in which direction to find them, the historical information behind our understanding of each element, the many, many applications, and so on.*
- (August 5th, 02006): #electronics chat website, wiki and all.
- (August 5th, 02006): TODO: timeline of microdevice manufacturing and fabrication technology
- (August 5th, 02006): suggestion: external links to have '-' next to them if content not yet added, if content has been added then a '+' should be added next to them. Actually, let us make this slightly more complex. External links with - imply that it has yet to be touched at all. External links with + imply that the content has been glanced at. External links with ! have been read and the content has been added. External links with * after the link have been recursively accessed. A combination of !*- is meant to serve as a reminder that the content has been added, the links have been explored, however those links have not been explored. Similarly, !*+- implies that the links at the page have been glanced at, but their content not accessed, et cetera. Note that a link followed by * is probably a reminder that the content has been recursively accessed and to not bother going further.
- (August 5th, 02006): Tor [1-]
- `Tor is a network of virtual tunnels that allows people and groups to improve their privacy and security on the Internet. `
- This may be an implementation of some software that I and some others have anticipated (search term: ForumOS)
- (August 5th, 02006): TODO: Organize chemical information by generating a list of the chemical elements with standard information. There is some information about silicon at this page that is not mentioned on the periodic table of elements.
- (August 5th, 02006): TODO: process these bookmarks (found by a reverse link lookup to Sahtouris' content)