Thursday, 28 January 2016

Article reading statistics + articles with zero comments

This post shares recent trends in VPHA reading. Main findings:

  • The number of comments obtained has been nicely increasing since December 2015. We still face a serious challenge, though, in getting the planned three comments per article by something like May 2016.
  • There are at the moment as many as ninety (90) articles listed with no comments yet. 

In the weeks to come, we should try to prioritize the reading and commenting of articles with no comments yet (although people can and it is useful also continue to read other papers, too). A list of publications with zero comments is shown below. Most of the remaining articles with zero comments are available only in Russian. Most are journal articles but some are conference papers and there are many theses, too. Some Finnish theses are also still included in this list with zero comments, and there are a few publications in English, German, and Bulgarian remaining, too.


Monday, 25 January 2016

ALD history blog is three months old - statistics shared

Today, it is exactly three months since the ALD History Blog was created. After several months of hesitating (related LinkedIn post, March 14, 2015), I started the blog on October 25, 2015, as the need to share the progress in Virtual Project on the History of ALD (VPHA) and in general in understanding the history of ALD become overwhelming with the ALD Russia workshop (travel report here). In hindsight, I am glad that I started the blog: there has been plenty of topics to write about (I'd write more if I had more time) and the blog has found an audience, with an all-time average of 44 pageviews per day. For communicating the advances of VPHA to the virtual project group efficiently, the blog is irreplaceable.

Below, I share the all-time (=three-month) statistics of the ALD History Blog as enabled by Blogger: Overview, Post statistics, Traffic sources, and Audience.  Top-five countries in pageviews, in descending order, are: Finland, United States, Germany, France, and Russia. Recognized important referring sites are, for example, Twitter, LinkedIn, BALD Engineering blog and

Last, I want to share my latest topic of hesitation. Should/could VPHA have its own page in Wikipedia? Opinions; pros and cons? You can share your views e.g. in discussion chain started a few days ago in Twitter.  

Top 10 viewer countries of the ALD History Blog all time Oct 25, 2015 to Jan 25, 2016.

Wikipedia ALD history description updated

As part of the Wikipedia update task (#11 in the VPHA Publication Plan,, a major update has been made to the History description in the ALD page, I have made the update during January 23-24 (username rlpuu), with details checked and additions proposed by Tuomo Suntola. The most important change was that now, it is clearly stated that ALD has developed through two independent discoveries. Also, the notation has been removed that the concept of ALD would have been proposed in the thesis of Aleskovskii in 1952 (the matrix hypothesis was there, but no proposal for ALD yet).

Obviously, the description can be still improved in many ways. I will most likely be making further edits later, and as Wikipedia is a free encyclopedia, everyone can further improve the text. For those intending editing, it is good to read through the Wikipedia principles described in the five pillars of Wikipedia. Wikipedia contents are free to use but still copyrighted, so when re-using material from Wikipedia, one is required to provide credit to the authors by e.g. linking to the Wikipedia page, see Reusing Wikipedia contents and Reuser's rights and obligations.

Friday, 22 January 2016

Wikimedia Commons has new categories: Atomic Layer Deposition and Tuomo Suntola

Categories are an easy way to organize files in Wikimedia Commons. Wikimedia Commons, again, is an easy way to store files of general use in Wikipedia, to be used in related texts written on the same topic in different languages. As part of VPHA Wikipedia update (#11 in our Publication Plan), two new categories have been created in Wikimedia Commons:

If you add files to Wikimedia Commons, please remember to add the right categories, to find back files easily.

Virtual Project on the History of ALD (VPHA) - in atmosphere of Openness, Respect, and Trust

VPHA status update 2016-01-22

The status update below was sent to 45 co-authors and 32 prospective co-authors.
Dear current and prospective VPHA co-authors,

VPHA progresses. In this update, you find information on:

  1. New: ALD thesis list
  2. Questions to the ALD History review
  3. Wikipedia update
  4. ALD terminology discussion
  5. ALD 2016 abstract
  6. VPHA in numbers

Wednesday, 20 January 2016

Wikipedia update: English page and photograph for Tuomo Suntola

Recent progress in the Wikipedia update (#11 in the VPHA Publication Plan):

  1. Tuomo Suntola has a Wikipedia page in English: Thank you to Angel Yanguas-Gil for creating this first version of the Suntola page. Updates are to come. 
  2. A photograph of Suntola has been uploaded to Wikimedia Commons for everyone's use:,_2014.JPG. This photo was taken by myself at the Baltic ALD 2014 conference in Helsinki during Suntola's opening invited talk, and I have now donated it to the Wikipedia update effort. The photo has been uploaded with a Creative Commons licence, and the copyright line needs to be remembered in further use. I think this will do: "Author: Riikka Puurunen. This file is licensed under the Creative Commons Attribution-Share Alike 4.0 Internationallicense". Tuomo himself has also approved the use and uploading of the photograph to Wikimedia Commons.   

Tuomo Suntola giving the opening invited talk entitled "From ideas to global industry - 40 years of ALD in Finland" at the International Baltic ALD conference, May 12, 2014, in Helsinki, Finland. Photo by Riikka Puurunen. Released to Wikimedia Commons on January 20, 2016.

Virtual Project on the History of ALD (VPHA) - in atmosphere of Openness, Respect, and Trust

Tuesday, 19 January 2016

ALD terminology discussion: ALD Window - 2

Thank you for the discussion on the ALD-specific term, "ALD Window", as started in As confirmed in LinkedIn,, this term has been created by Tuomo Suntola.

To check the first usage, I contacted Suntola himself. For certain, ALD Window has been presented in the 1989 review. However, according to Suntola it is likely that the term has been in use already in early 1980s. Below is an image which is probably a mid-step in the evolution towards the ALD window concept that we now know. It is from 1981 from Suntola's invited talk at the ICVGE-5 conference.

Scanned slide from the invited presentation T. Suntola, "Atomic Layer Epitaxy", Tech. Digest of ICVGE-5, San Diego, 1981. Provided by Tuomo Suntola.

Under construction in VPHA: ALD Thesis List

Working towards the VPHA ALD History Review (Item #10 in the VPHA Publication Plan), we have in VPHA started to build a list of doctoral theses on ALD worldwide. We do this in file "VPHA-ALD-thesis-list", you find a link at It is a challenge, and perhaps impossible, to create a complete list. Nevertheless, we will give it a try.

As the first step, information already collected on the Finnish and Soviet/Russian theses was combined (sources: FinALD40 exhibition, ML essay)---thank you Oksana for doing this. Currently, the list contains 134 doctoral theses. Next step is to update the list with theses from other countries: for example, Australia, Belgium, Bulgaria, Canada, China, Estonia, Germany, France, Korea, India, Japan, Norway, Sweden, The Netherlands, Turkey, Ukraine, United Kingdom, United States...  (excuses already for the countries missing from the list).

Friday, 15 January 2016

Wikipedia 15 years - status of WikiALD update

Wikipedia was launched exactly fifteen years ago, on January 15, 2001 ( Wikipedia and VPHA share much of the same philosophy: both are worldwide efforts based on voluntary work, and both are aimed for collectively creating correct information for everyone's benefit. Today should be a good day to share what we have done already in VPHA related to the Wikipedia ALD history update, Item #11 in the VPHA Publication Plan. These are easy to track back through "view history" tab in Wikipedia.

Thursday, 14 January 2016

ALD terminology discussion: ALD Window

"ALD window" (sometimes, ALD temperature window) is a term used widely in ALD literature.

Although this term is widely used and specific to ALD, rarely, an original source is pointed out.

Who created this term, and when? Can the first (public, written) record for this be tracked back? How was ALD Window originally defined and how did it look like? Nowadays, exactly how it is described, may tend to differ slightly from one source to the other.

I am asking, because by the time that we will write the ALD History Review (#10 in the VPHA Publication Plan,, we should know.

VPHA status update email 2016-01-14

The status update below was sent to 42 co-authors and 33 prospective co-authors. 
Dear current and prospective VPHA co-authors,

VPHA progresses. A short status update again, with the following topics

  1. Questions for the ALD History Review
  2. VPHA reading, first priority: publications with no comments yet
  3. How to navigate in massive VPHA files
  4. Other recent ALD History Blog posts

Sunday, 10 January 2016

How to navigate in massive VPHA co-editing files

The main co-editing file of Virtual Project on the History of ALD (VPHA), the ALD-history-evolving-file, has at the moment 177 pages. In some months, it will have maybe two hundred pages more. How can you navigate in a giant file like this?

The easiest way that I have found is to use the search function built in every browser (shortcut typically: CRTL + f). In VPHA, each historical ALD publication has (or will get) a unique code. (In addition to navigation, the unique codes will also be used for writing the ALD History Review - more on that later.) These codes are given in parentheses, like this: {Sveshnikova1970b} en ru, both in the ALD-history-evolving-file and the VPHA-reading-overview-file. The languages, in which we have the publication available, are shown after the code itself (this is the aim, at least).

Following a blog by email, how it works

The service used for ALD History Blog, "Blogger", offers the possibility of getting new posts directly in your mailbox. I have tested how this works with ALD History Blog ( as well as with the highly recommended BALD Engineering blog ( Conclusion is that email subscription works very well and I can recommend it to others.

During the first half of 2016, VPHA will be active and there will be many new posts, each sharing something new and taking VPHA in small steps forward. For those not actively following professional social media (LinkedIn and/or Twitter), email subscription would be an easy way to stay up to date with new information.

Saturday, 9 January 2016

Historical ALD publications with more than three VPHA comments

Continuing on the previous post, here is finally a list of historical ALD publications which have (according to the current bookkeeping) received more comments in VPHA reading than the target number of three. This list contains ten (10) publications at the moment.

I would not yet call this a recommended reading list yet for the history of ALD, as the work is still very much on-going --- about 40% of the effort is now done. It does seem obvious, however, that in the end of VPHA the most interesting/important (and maybe also at the same time accessible) articles will have received more comments than average and that one kind of recommendation for "early ALD history reading" can ben created merely on the basis of the number of comments given for each publication.

Historical ALD publications with three VPHA comments

Continuing on the previous post listing publications in VPHA that have received two comments, the list below shows publications in the ALD-history-evolving-file that have received three comments. We aim for three reads & comments per publication, which means that these publications should have enough reads. One can still read and comment further. Especially in cases where it looks like the article will not be included in the final ALD literature list (e.g., Kohlschutter1950), it will be good to have many opinions, to be sure. This list contains 21 items.

Historical ALD publications with two VPHA comments

Now that I have listed the articles in ALD-history-evolving-file with zero or one comment, for the sake of completeness, it will be good to list also those with two or more comments for the same moment. The publications below have received two comments in the ALD-history-evolving-file in the Virtual Project on the History of ALD (VPHA). Thus, one is missing for each item, if we aim for three reads & comments per publication. There are 69 publications in this list.

Historical ALD articles with one comment

Going though the table of historical ALD articles with no comments yet in VPHA (, I noticed that there are few publications for English-speakers to read. Likely >90% of the publications are in Russian. There are also theses in Finnish, and some publications in German and Bulgarian.

To facilitate the VPHA reading progress, it should be useful to point publications for English-speakers, too. So, I created another list of articles in ALD-history-evolving-file that at the moment have one comment. There are 157 such articles at the moment, listed below. Let's make some progress for these! The target is that, by the end of VPHA, each publication has at least three comments.

Friday, 8 January 2016

Historical ALD articles with no VPHA comments yet

Today, I had a look at the VPHA-reading-overview-file, specifically finding the publications which have no comments in VPHA yet - at the moment there are 90 such publications. Below you find the list copy-pasted as table --- my excuses, if this does not show up well in the blog. If you see here articles that are interesting to you, please help, read them, and share your comments.

List of ALD reviews has been updated

Today the page had a major upgrade, as well over 20 review articles were added for years 2003 to 2015. This update was made on the basis of input sent by Miika Mattinen from the University of Helsinki - thank you Miika for sending the info! I will keep on making updates, so if you see missing items, please send to me to, or leave a comment to the posts or to the page of review articles.

Virtual Project on the History of ALD (VPHA) - in atmosphere of Openness, Respect, and Trust

VPHA status update email 2016-01-08

The status update below was sent to 41 co-authors and 33 prospective co-authors. 
Dear VPHA co-authors and prospective co-authors,

This is the first status update email of 2016 and contains information on the following items. A copy the previous status update, sent on December 17, 2015, can be found in the ALD History Blog (with just some sensitive information removed).  

  1. Molecular Layering essay has been published
  2. Questions for the ALD History Review: deadline Jan 10
  3. New participants to join the VPHA ALD 2016 Ireland abstract: deadline Feb 7
  4. New co-authors welcome to the ALD history review
  5. History of ALD terminology
  6. VPHA in numbers - positive progress and still a lot to do
  7. More ALD History Blog posts

Thursday, 7 January 2016

New type of statistics for ALD-history-evolving-file

Good news: I have learnt how one can collect article reading statistics from the VPHA-reading-overview-file with Google spreadsheets functions. This makes it easy to visualise the status of commenting, whether individual papers have 0, 1, 2, 3, or 3+ comments. Below you find the current situation. With time, I plan to report on trends on how the reading evolves.
Statistics of the number of VPHA comments per ALD publication, on the basis of VPHA-reading-overview-file, as of 7.1.2016. Made with Google spreadsheets. 

Wednesday, 6 January 2016

Countries and VPHA reading statistics, 2016-01-06

The number of co-authors in the ALD-history-evolving-file is now 41, from 12 countries (Estonia, Finland, France, Germany, Ireland, Italy, Poland, Russia, Sweden, The Netherlands, Turkey). The countries are highlighted in the next map and the exact number of authors per country is shown in the pie graph below.

Author map of ALD-history-evolving-file, January 6, 2016. Shades of grey show countries with VPHA co-authors; the darker the colour, the more there are participating co-authors. Map created with Google spreadsheets.
Pie graph of authors in the ALD-history-evolving-file, January 6, 2016. Created with Google spreadsheets. 

Tuesday, 5 January 2016

VPHA abstract to ALD 2016 Ireland - DL Feb 7

The webpage of ALD 2016 in Dublin, Ireland, July 24-27, has been updated and abstract submission is open.

From VPHA, there will be one abstract to ALD 2016 (Item #9 in the Publication Plan). The contents of the presentation will be a summary of the historical ALD papers and a recommended reading list, created together by the VPHA group, based on the contents of the ALD-history-evolving-file. All those will be listed as authors of the presentation, who have participated in the voluntary VPHA reading and left at least one comment in the ALD-history-evolving-file by the time of sending the abstract. We have at the moment 41 co-authors from 12 countries (Poland joined recently).

The deadline of ALD 2016 is February 14. The VPHA internal deadline should be somewhat earlier; let us make this one week. If you'd like to join the VPHA abstract as an author, please make your first comment in the ALD-history-evolving-file no later than on February 7, 2016. People can of course join the voluntary VPHA reading later than this, too, only then their name will not appear in the ALD 2016 abstract.

Virtual Project on the History of ALD (VPHA) - in atmosphere of Openness, Respect, and Trust

Monday, 4 January 2016

On the importance of defining the problem - What information is missing about the early days of ALD?

"It isn't that they can't see the solution. It is that they can't see the problem." These words have influenced me ever since I red them as a student of chemical engineering at Helsinki University of Technology (nowadays Aalto University) in mid-1990s. The words were written at the beginning of a chapter in the book of Chemical Reaction Engineering;* I was majoring in industrial chemistry with professor Outi Krause (of ALD, I knew nothing yet). I may have forgotten everything else that was written in that book, but these words made a permanent impact on me.

Beginning of a chapter in the book "Elements of Chemical Reaction Engineering" by H. Scott Fogler.* These words by G. K. Chesterton have stayed in my mind ever since seeing this. Photo by Riikka Puurunen. 

Virtual Project on the History of ALD (VPHA) started from a question: "What are the "Molecular layering" papers by Koltsov from "early 1960's?" This question I asked in the ALD - Atomic Layer Deposition LinkedIn group in the spring 2013. One can still find the question and the lively discussion that followed, here:
These words had caught my attention in the ALD Hall of Fame by; they disturbed me as I did not know what exactly they referred to.

ALD terminology discussion: Atomic Layer Deposition

Everyone uses term "Atomic Layer Deposition (ALD)" nowadays, but this is not how the technique was invented. Originally, the technology was called Atomic Layer Epitaxy (in Finland) and Molecular Layering - or actually, Molekulyarnoe Naslaivanie (in Russia). 

What is the first documented use of the term ALD? I am asking, because I don't know --- not yet. By the time of writing the "ALD History Review" (number 10 in the VPHA Publication Plan), we should know. Preparations for the review are now just starting, and more co-authors are welcome, as are also for the VPHA presentation at Ireland ALD 2016. 

Sunday, 3 January 2016

Baltic ALD 2015, Tartu: travel notes by Riikka Puurunen

The 13th International Baltic Conference on Atomic Layer Deposition, Baltic ALD 2015 was organised in Tartu, Estonia, September 28-29, 2015. Conference chairs were Prof. Jaan Aarik and Dr. Kaupo Kukli. Conference website: Right after the conference, on September 30, 2015, there was the yearly meeting day of the HERALD COST network on ALD (

I have not visited Tartu before, and it was very interesting to attend this Baltic ALD conference in the historical city of Tartu, where the first report of ALD (then, ALE) is from year 1983. This post in the ALD History Blog finally shares my travel notes from Baltic ALD, both as text and photos. BALD Engineering collected a "photo show" during the event, which can be found here. In Twitter, post and pictures from Baltic ALD conferences can be found back with hashtag #BalticALD.

Colours, colours! The Baltic ALD 2015 conference was organized at the Physicum building of Tartu University. Photo by Riikka Puurunen.