Sulfur Hexafluoride...

Yep, its used in a RIE (reactive ion etcher) to etch patterns into Si wafers. Used to do that when I was in grad school.

 

I would not be surprised that China, Hong Kong, and Taiwan are now major emitters of SFl6

 

True, most wafer fab is done in the far East now. Our sister company that did semiconductors had them fabbed in Taiwan and did the packaging assembly in Malaysia. They took what little assembly work we had left and sent it to Malaysia when they shut our facility down in October.

 

Well, that sucks. Lot of skilled folks lost their jobs

A lot of former IC plants in the US and Canada are - or should be - SuperFund sites due to the high level of heavy metals and fluoridated solvent contamination

For the same reason, FUDS (Formerly Used Defense Site) are also high on the list of SuperFund sites. Things like cadmium from Ni-Cd batteries, carbon tetrachloride, trichloroethylene, perchloroethylene, etc, tend to remain in soils for a long, long time

 

Yep, [ame=http://en.wikipedia.org/wiki/Trichloroethylene]TCE[/ame] is nasty sh!t. We used it to clean wafers back in grad school days. I hated that stuff. We used it in a negative pressure fume hood, but I could still taste the fumes from it. I was never interested in working in a fab after my college experience.

 

P.S. Does anyone know why links don't post right anymore? That is the second time I posted a referenced link and it ignored my reference and doubled up the Wikipedia title instead?????

 

I do not know, I've been posting a lot of links including my new PhotoBucket one, and everything seems fine

Do what I do in that situation: try not to drink so heavily right before posting

 

Maybe I need to drink more. So far it has only happened when I'm sober.

Anyway, lots of nasty chemicals are used in semiconductor manufacturing.

[sarcasm] I guess it is really best to do it in a region of the world where human rights are respected and environmental laws are so rigidly followed. [/sarcasm]

 

Actually it is. One of the unusual lessons of my life (i.e. one that is non-intuitive) is that very high standards in manufacturing result in very profitable industries.

Where it really showed up was in the US built nuclear submarines. The Reactor spaces were engineered to very high standards, such as all coolant piping being welded and inspected for every joint and the main coolant pumps using only water for lubrication. Unlike this, the engineering spaces (i.e. the steam turbines and electrical equipment) were built to much more "forgiving standards". Over the life of the sub, 95% of everything that needed repairs and repair parts was for the non-nuclear stuff. This cost quite a bit of money over the 30 year life of a submarine.

One a closer to home example, how much has the performance and reputation of high quality helped Toyota? I bet it cost them more up front.

 

I think you may have misinterpreted my comment. I agree that it really isn't much more expensive to do something the "right" way than it is to cut corners. And in the long run, it is better to do it the right way because your customers will keep coming back. If you do it wrong, your customers will go to someone else.

What I meant with my sarcastic comment was that the semiconductor industry is leaving the US and going to other countries where there is a cheaper labor force and more lax environmental regulations.

 

The sarcasm switch gave me a clue, but I could not stop myself from responding to the opening provided.

About 25 years ago, the US semiconductor industry was very much a leader since the leadership was "engineering" oriented. But two decades is enough time for most firms to become "finance" oriented....hence the US decay.

 

The sad part is that because California is trying to do the right thing - control SF6 emissions because they are potent greenhouse gases - they will end up accelerating the shift of semiconductor manufacturing overseas.

So, what to do, allow companies to foul the environment in the States, or push them to foul the environment somewhere else?

 

Hmmph, sounds like Texas!

 

That hits close to home. My first job out of college was for Peterbilt which used to be located in California. They closed the Newark, California assembly plant in 1986. One of the rumors was that they were limited in build rate by the amount of paint emissions. They eventually moved the company headquarters to Denton, TX.

I just heard a week or so ago that they are going to close the Madison, Tennessee facility too. So all of the production will be in Texas where the paint emissions are apparently not an issue.

 

Yep that's how our population grew from 10 million to 20 million from 1970 to 2000. They (politicians and lobbyists) entice companies to relocate here by promising lax pollution laws, low wages (few unions), cheap land etc. Oh and don't forget the bribes - er I mean tax abatements. Austin is littered with chip companies spewing who knows what into the air and many of them located here after being bribed with tax cuts. Samsung is one that comes to mind - like they need any kind of incentive. I live not far from a Freescale plant that is pretty old. I wonder sometimes what's in their exhaust, so to speak. SF6?

 

Actually, I would be more concerned about what might be in the water. TCE is very persistent and is a known carcinogen. Its was often used as a solvent for organic contamination.

Poughkeepsie Journal - February 20, 2005 - Cleanup guidelines lag

I live across the American River from Aerojet. The wells near Aerojet have become contaminated with TCE and other nasty chemicals as a result of rocket fuel manufacturing. The plume is apparently headed our way.

Aerojet - Wikipedia, the free encyclopedia

 

The footprint of different types of chemicals varies tremendously. SF6 is global because of its long atmospheric lifetime. T'won't matter a bit where the emissions take place.

In another example mentioned here (VOC) the footprint is much smaller because of hourse/days atmospheric lifetime.

 

A lot of hillbillies don't believe in things like "plumes," so obviously they don't exist. So they just stick their hands in their pockets and whistle.

When the more obvious cancer clusters and birth defect clusters show up, I guess everybody is expected to pack up and move. Unless they belong to a visible minority, in which case they can stay put

The cost to even attempt such remediation - eg air sparging, thermal soil treatment - is astronomical. Nobody seems to consider that when they claim that current environmental "standards" are too "tough"

What was considered "safe" 20-30 years ago is now a SuperFund site. The "cost" of tough environmental standards is far cheaper than the eventual cleanup

 

In the ultimate twist of irony, the generous taxpayer usually subsidizes a move overseas