HDTenEightyP/NetNews huggingface dataset:
From: 5916rahmank@vms.csd.mu.edu ( )
Newsgroups: sci.materials
Subject: Re: TEM samples
Date: 22 Dec 92 23:47:17 GMT
Reply-To: 5916rahmank@vms.csd.mu.edu
Distribution: usa
Organization: Department of EECE, Marquette University
NNTP-Posting-Host: vmsf.csd.mu.edu

In article <38005@uflorida.cis.ufl.edu>, sushilb@elm.circa.ufl.edu (Sushil Bharatan) writes:
>I require information on preparation of cross-sectional TEM samples
>of a semi-conductor material deposited on 0001 sapphire substrate.
>I am currently using a dicing saw for cutting strips that are about
>15 mils in width, but extensive cracking and chipping occur.
>Any information on dicing saw blade manufacturers and alternative
>methods is welcome.
>
>Thanks,
>Sushil Bharatan
>Dept. of Materials Science and Engineering,
>University of Florida.
>
>email:sushilb@elm.circa.ufl
>

	Sushil,

		Dicing saw may not be a good thing to use to cut non-metallic
	samples. Instead, you may use a diamond wafering blade with water as
	the cutting fluid. If you are going to make TEM samples, you need
	lot less thicker sample than 15 mil. It is wiser to cut a little
	thicker and then polish it to thin.

	-Anis.
Newsgroups: sci.materials
From: llh@cbnews.cb.att.com (lonnie.l.houck)
Subject: Re: Need to make a glass surface rough ...
Organization: AT&T
Distribution: usa
Date: Tue, 29 Dec 1992 15:49:43 GMT

In article <4rlrf7c@lynx.unm.edu> swami@chtm.eece.unm.edu (Swami srinivasan) writes:
>
>I need to make a 50 microns x 1000 microns section of glass surface
>ROUGH. I have  a mask with the required dimensions. Most etchants are
>"smooth", and I suspect the common HF based etchants are, too. Are there
>any wet chemical etchants that can be used? 
>  ... other  descriptions deleted ...

How about generating a pattern of randomly distributed 1 micron circles of a
metal on the glass. If the metal did not etch in HF or a F plasma then a very
rough surface could be generated by etching the glass around these circles.
With an isotropic etch and close spacing of the circles a field of random
glass cones would be produced. The metal could then be stripped off and
further processing could continue. Let me know whether this idea works out.

Lonnie Houck
llh@mvuzr.att.com
Newsgroups: sci.materials
From: tjdalton@athena.mit.edu (Transitive NightFall of Diamonds)
Subject: Polysilicon: Index of Refraction vs. Temp.
Followup-To: sender
Organization: Massachusetts Institute of Technology
Date: Mon, 21 Dec 1992 20:50:44 GMT

I'm looking for the index of refraction for polycrystalline silicon
as a function of temperature, in the range of -100C to +50C.
If anyone knows of a reference where I can find this, please email me.

Thanks,

	Tim

----
Timothy J. Dalton                                   tjdalton@mit.edu
MIT, Dept. of Chemical Engineering, Materials Etching Technology Lab
Newsgroups: sci.materials
From: tyadav@athena.mit.edu (T.Y.)
Subject: What could this be..........?
Organization: Massachusetts Institute of Technology
Date: Sat, 2 Jan 1993 20:18:59 GMT

==========================

 Are there materials,
 that are insulators at room temperature,
 and conductors at high temperatures?
 AND can remain intact and conductive at peak tempertures of 3800 F (2200 C)?
 Could electric field be suspended in space with electrodes of this material?

 If you know something, just press R. (or F, if you prefer).
 Thank you. :)

T.Y.
----
tyadav@athena.mit.edu
ps: No this isn't homework problem. Classes haven't begun yet!!
Newsgroups: sci.materials
Subject: In need of technical references !!!!!!
From: vxc15931@vax1.mankato.msus.edu
Date: 22 Dec 92 07:59:43 -0600
Organization: Mankato State University

Can anyone of you provide me with references to the use of ultrasonics in
cleaning the surface of a silicon wafer?  I am currently working on a design
project involving the use of a megasonic system (currently employed by FSI) in
removing surface particulates in the order of 0.15 microns and larger.

The system I am trying to design uses a Multiple Array Liquid Coupled
Transducer to generate the agitation necessary for particulate removal.  Right
now, I am seeking out the equations which I need for my MathCAD simulation.
Unfortunately, my university library is not exactly well-stocked with the
proper literature.

So if you could recommended any literature in the area of ultrasonics being
used for surface decontamination (?), I would appreciate it very much.

Let me know if I haven't made my needs clear enough.

Thanks in advance!

==================

Jose' R.C. Cruz
Graduate Assistant
Department of Physics, Engineering and Technology
Mankato State University
Mankato, MN 56001

==================

You may either post your responses in this newsgroup or E-Mail it to me.  The
latter is preferable.
From: 5916rahmank@vms.csd.mu.edu ( )
Newsgroups: sci.materials
Subject: Re: information wanted on cubic zirconia
Date: 23 Dec 1992 15:27:20 GMT
Organization: Department of EECE, Marquette University
Reply-To: 5916rahmank@vms.csd.mu.edu
NNTP-Posting-Host: vmsf.csd.mu.edu

In article <19DEC92170737@fnalh.fnal.gov> boswell@fnalh.fnal.gov writes:
>
>Hello,
>  I am working with silicon diode particle detectors, and know
>of some work with diamond, which is hard to make into a detector
>because a single crystal is more efficient, whereas the depositio
>diamond traps charge at the crystal boundaries.  This got
>me thinking:  what are the electrical properties
>of cubic zirconia, and how is it made?  If you know
>where to look, I would appreciate the info.
>
>	Chris Boswell

---------------------------------------------

	I am not too much familiar with ZrO2, but I know its electrical
	properties are complicated. Mostly it is an ionic conductor. Being
	a non-stoichiometric material, it conducts via oxygen ion transpor-
	tation. Some doped zirconia (e.g., Yittrium or Cerium doped) are
	mixed conductor and point defects (such as vacancies) play an
	important role to determine its electrical properties.

	I heard ZrO2 is used in some oxygen sensors, the ones that are
	used at higher temperatures.

	-Anis.
Newsgroups: sci.materials
From: Graham_Parkinson@mindlink.bc.ca (Graham Parkinson)
Subject: Re: Hazardous Waste Newsgroup?
Organization: MIND LINK! - British Columbia, Canada
Date: Tue, 29 Dec 1992 22:48:44 GMT

> Kent Goeking writes:
>
> Msg-ID: <Bzz5r7.H3I@creare.com>
> Posted: 28 Dec 92 15:01:53 GMT
>
> Org.  : Creare Inc., Hanover, NH
>
> In article <1992Dec21.110124.543@doc.bmd.trw.com> dsanders@doc.bmd.trw.com
> writes:
> >Hello readers,
> >
> >I am trying to locate a newsgroup or forum for the discussion of topics
> >related to hazardous and toxic waste handling, storage, and disposal.
> >
> >Dale_Sanders@oz.bmd.trw.com                   Ogden, UT 84403
> >***************************************************************************
> ****
>
> fit though or what it should be called.  Perhaps it could be put as a



Agreed - One more interested in a hazardous wastes newsgroup as we spend
Agreed - we spend alot of our time looking for buried hazardous wastes at old
         industrial sites with geophysical techniques such as EM etc.

--
******************************************************************
*  Graham Parkinson - Frontier GeoSciences, Vancouver BC CANADA  *
*  uunet Graham_Parkinson@Mindlink.bc.ca                         *
******************************************************************
Newsgroups: sci.materials
From: dgm@cs.sfu.ca (Dennis Michaelson)
Subject: Re: Need to make a glass surface rough ...
Keywords: glass etching microelectronics
Organization: CSS, Simon Fraser University, Burnaby, B.C., Canada
Date: Tue, 29 Dec 1992 00:17:10 GMT

In article <6rlracd@lynx.unm.edu> swami@chtm.eece.unm.edu (Swami srinivasan) writes:
>
>I need to make a 50 microns x 1000 microns section of glass surface
>ROUGH. I have  a mask with the required dimensions. Most etchants are
>"smooth", and I suspect the common HF based etchants are, too. Are there
>any wet chemical etchants that can be used? 

A suggestion borrowed from the craft of decorative glass etching would
be to mix the HF with a biflouride, such as ammonium biflouride, which
will leave a frosted surface.  Unfortunately I do not know the proper
mix ratio, but checking with the glassblowing shop in your Chemistry
department may yield the answer, or look up glass etching in a public
library under arts and crafts.

Dennis Michaelson
School of Engineering Science
Simon Fraser University
Burnaby, B.C.  Canada
dgm@sfu.ca
Xref: sparky sci.materials:1039 sci.chem:5545
From: kwg@creare.com (Kent Goeking)
Newsgroups: sci.materials,sci.chem
Subject: SEM of lithium?
Date: 22 Dec 92 14:14:28 GMT
Reply-To: kwg@creare.com
Followup-To: sci.materials
Organization: Creare Inc., Hanover, NH


   I would like to hear if anyone has any experience in preparing moisture
sensitive samples for SEM examination.  In particular I would like to
examine the interface between a piece of lithium and a polymer electrolyte
to understand the interface phenomena that is responsible for degredation
in lithium based batteries.

   Unfortunately, lithium reacts vigerously with water and the moisture
present in the air would destroy any interesting interface microstructures
before I got a chance to look at them.  Is it possible to prepare the
sample in-situ?  I mean while in the SEM vacuum chamber?  Any ideas or
reference suggestions appreciated.

Thanks,

Kent Goeking
Creare Inc.
kwg@creare.com  
Newsgroups: sci.materials
From: chenye@gn.ecn.purdue.edu (YM Chen)
Subject: Static charges on 1 micro alumina powder??
Organization: Purdue University Engineering Computer Network
Date: Mon, 21 Dec 92 19:51:27 GMT

Hello netter,

Recenterly, we are starting to use a small particle to polish ceramics.
Unfortunately, the particles (1 micron alumina) have a lot of static
charges and, therefore, cause many bubble in the slurry.
we have talked to the sales representative of the company who made this
particles and get no answer.  Is there anyone have any suggestion to
remove the static charges in the particles?
Note that when we use larger particle size, there is no static charges
problem.  Any suggestion will be appreciated.

Thanks.

Yenmeng Chen

-- 
chenye@ecn.purdue.edu
1287 GRISSOM HALL
SCHOOL OF INDUSTRIAL ENGINEERING
------------------------------------------------------------------------
Newsgroups: sci.materials
From: llh@cbnews.cb.att.com (lonnie.l.houck)
Subject: Re: Static charges on 1 micro alumina powder??
Organization: AT&T
Date: Tue, 29 Dec 1992 15:28:10 GMT

In article <1992Dec21.195127.11649@gn.ecn.purdue.edu> chenye@gn.ecn.purdue.edu (YM Chen) writes:
>Recenterly, we are starting to use a small particle to polish ceramics.
>Unfortunately, the particles (1 micron alumina) have a lot of static
>charges and, therefore, cause many bubble in the slurry.
>we have talked to the sales representative of the company who made this
>particles and get no answer.  Is there anyone have any suggestion to
>remove the static charges in the particles?

There are several companies that make air ionization equipment. By gently
passing this over your powder, most of the static charge can be neutralized.
If a large quantity of powder needs to be neutralized one could set up some
way of "bubbling" ionized air or nitrogen through a container of powder. One
should be careful in how the powders are handled after neutralization. Any
vigorous motion could quickly build up charges again. Even the simple act of
pouring the powder might charge it to unacceptable levels. Pouring may need to
be done in a gentle wash of ionized air.

Two examples of companies with air ionizers are 
     Ion Systems
     Static Control Systems

Check in the trade magazines Buying Guides (Microcontamination, Clean Rooms,
Semiconductor International, etc.) for other companies and phone numbers. 
Good Luck.

Lonnie Houck
llh@mvuzr.att.com
From: yuanj@ucbeh.san.uc.edu
Newsgroups: sci.materials
Subject: Re: Need to make a glass surface rough ...
Date: 27 Dec 92 09:31:11 EST
Followup-To: swami@chtm.eece.unm.edu, swami@triton.unm.edu,sci.materials
Distribution: world
Organization: Univ. of Cincinnati

In article <6rlracd@lynx.unm.edu>, swami@chtm.eece.unm.edu (Swami srinivasan) 
writes:
> 
> I need to make a 50 microns x 1000 microns section of glass surface
> ROUGH. I have  a mask with the required dimensions. Most etchants are
... the purpose was to make a defusive area, ...... 

Could you deposit something on the surface to make it defusive?  For example,
some Si.

J. Y.
Newsgroups: sci.materials
Subject: Technical references for wafer-cleaning using ultrasonics
From: vxc15931@vax1.mankato.msus.edu
Date: 27 Dec 92 16:51:17 -0600
Organization: Mankato State University

Can anyone of you provide me with references to the use of ultrasonics in
cleaning the surface of a silicon wafer?  I am currently working on a design
project involving the use of a megasonic system (currently employed by FSI) in
removing surface particulates in the order of 0.15 microns and larger.

The system I am trying to design uses a Multiple Array Liquid Coupled
Transducer to generate the agitation necessary for particulate removal.  Right
now, I am seeking out the equations which I need for my MathCAD simulation.
Unfortunately, my university library is not exactly well-stocked with the
proper literature.

So if you could recommended any literature in the area of ultrasonics being
used for surface decontamination (?), I would appreciate it very much.

Let me know if I haven't made my needs clear enough.

Thanks in advance!

==================

Jose' R.C. Cruz
Graduate Assistant
Department of Physics, Engineering and Technology
Mankato State University
Mankato, MN 56001

==================

You may either post your responses in this newsgroup or E-Mail it to me.  The
latter is preferable.
From: kwg@creare.com (Kent Goeking)
Newsgroups: sci.materials
Subject: Re: information wanted on cubic zirconia
Keywords: cubic zirconia
Date: 22 Dec 92 14:06:30 GMT
Reply-To: kwg@spock (Kent Goeking)
Organization: Creare Inc., Hanover, NH

In article <19DEC92170737@fnalh.fnal.gov> boswell@fnalh.fnal.gov writes:
>
>Hello,
>  I am working with silicon diode particle detectors, and know
>of some work with diamond, which is hard to make into a detector
>because a single crystal is more efficient, whereas the depositio
>diamond traps charge at the crystal boundaries.  This got
>me thinking:  what are the electrical properties
>of cubic zirconia, and how is it made?  If you know
>where to look, I would appreciate the info.
>
>	Chris Boswell
>
Just because cubic zirconia has an index of refraction and birefringence
properties similar to diamond, don't assume its electronic properties are
similar.  I don't know for certain but I would assume that c-ZrO2 is a
really great insulator and not a semiconductor like diamond, silicon, etc.

Cubic zirconia is made by a crystal growth technique called skull melting.
The problem with growing c-ZrO2 crystals (which are typically stabilized
with small additions of Y or Mg) is its very high melting point (>2700 C)
compared to silicon's m.p. of 1410 C for example.  At such high
temperatures it is difficult (some say impossible) to find a decent
material to use as a crucible to contain the molten zirconium oxide.  This
is where the skull melting technique has an advantage. 

In skull melting, the material to be grown acts as its own crucible.  This
is done by RF heating the melt while simultaneously water cooling the
circumference.  Thus, the oxide becomes liquid in the center (due to
capacitive heating effects of the RF field) but remains solid at the edges
thereby forming its own crucible.  It was the development of this technique
that made someone a millionaire because it enabled the growth of cubic
zirconia and the jewerly market has never been the same since.

Glad you asked.

Kent Goeking
Creare Inc.
kwg@creare.com
Newsgroups: sci.materials
From: dabbott@augean.eleceng.adelaide.edu.AU (Derek Abbott)
Subject: Minority Carrier Diffusion length
Organization: Electrical and Electronic Eng., University of Adelaide
Date: Fri, 18 Dec 1992 06:06:33 GMT


Does anyone know of any references that discuss diffusion length
in SemiInsulators?
From: kwg@creare.com (Kent Goeking)
Newsgroups: sci.materials
Subject: Re: Superconductors and Piezoelectrics
Date: 28 Dec 92 15:23:22 GMT
Reply-To: kwg@spock.creare.com (Kent Goeking)
Organization: Creare Inc., Hanover, NH

In article <1992Dec21.005356.18395@athena.mit.edu> solman@athena.mit.edu (Jason W Solinsky) writes:
>Hi all.
>
>I have a couple of questions that I was wondering if anybody here could answer.
>
>First off, I'm curious about whether NbN is a superconductor. I just saw a
>paper which said it was, and that its acoustic attenuation was dramatically
>effected by the superconducting transition, falling to zero a degrees beneath
>the Tc. I had some reason to believe that NbN was NOT a superconductor
>and I'd appreciate it if anybody here can clarify that for me.
>
... second question deleted... (i.e. I don't know)
>
>Jason W. Solinsky

According to my handy book of knowledge (CRC Chemistry and Physics
Handbook) NbN or rather NNb is a superconductor with the following
transition temperatures:

     NNb (whiskers)              10-14.5   K
     NNb (diffusion wires)       16.10     K
     NNb (film)                  6-9       K
     N0.988Nb                    14.9      K
     N0.824-0.988Nb              14.4-15.3 K
     N0.70-0.795Nb               11.3-12.9 K

Hope this helps,

Kent Goeking
Creare Inc.
kwg@spock.creare.com
Newsgroups: sci.materials
From: tdtyl@eng.clemson.edu (Ted Taylor)
Subject: Re: Looking for low-loss microwave dielectrics
Reply-To: tdtyl@eng.clemson.edu
Organization: College of Engineering, Clemson Univ.
Date: Tue, 22 Dec 1992 17:42:46 GMT

In article 7602@dove.nist.gov, rochford@bldrdoc.gov (Kent Rochford 303-497-5170) writes:
>I need a low loss ( loss tangent <.0005 ) RF to microwave (1MHz
>to a few GHz) dielectric, preferably with a dielectric constant
>around 4.  Please send me any info on suppliers, vendors, or
>handbooks that might help.  Thanks.
>
>-- 
>Kent Rochford  NIST  Boulder, CO  rochford@bldrdoc.gov
>"No matter where you go, there you are" B. Banzai


If I were you, I'd try fused silica.  You can obtain this material from companies 
such as GE and Corning Glass Works.
From: khartman@fnalnb.fnal.gov
Newsgroups: sci.materials
Subject: Re: Need to make a glass surface rough ...
Date: 1 Jan 93 21:31:11 -0600
Organization: Fermi National Accelerator Lab
NNTP-Posting-Host: fnalnb.fnal.gov

In article <4rlrf7c@lynx.unm.edu>, swami@chtm.eece.unm.edu (Swami srinivasan) 
writes:
> 
> I need to make a 50 microns x 1000 microns section of glass surface
> ROUGH. I have  a mask with the required dimensions. Most etchants are
> "smooth", and I suspect the common HF based etchants are, too. Are there
> any wet chemical etchants that can be used? 
> 					I also have access to RIE
> and RIBE systems, but cannot think of any obvious ways to use them to
> make a rough surface - so far, we have always wanted a smooth etch!
> We have a full-fledged cleanroom with the usual equipment, so we should
> be able to try out most  suggestions, including uncertain leads.
> 
> We are trying to make a low reflectivity strip on a mirror. This 
> will be used in an external cavity configuration. Initially we thought
> of making crossed diffraction gratings, but there will still be a zero
> order reflection.. and grating fabrication is a little involved. Hence
> we are trying to find ways to make the surface diffusive using some 
> form of etching, with the dimensions decided by a mask.
> 
> Any suggestions will be helpful. Thanks!
> 
> 							     swami


	You might try using gaseous HF instead of aqueous HF.  I recall 
reading somewhere that aqueous HF will leave a "clearer" (smoother?) etch,
while the gas was used to frost light bulbs.  This might provide a coarser
surface.

	Form the gaseous HF by mixing Sodium Fluoride and concentrated
Sulfuric Acid in a lead dish (keep this in a fume hood).


 
> =======================================================================
> swaminathan srinivasan
> center for high tech materials
> eece,university of new mexico,
> albuquerque, nm 87131, usa			swami@chtm.eece.unm.edu
> ========================================================================
> 						


Ken
From: swami@chtm.eece.unm.edu (Swami srinivasan)
Newsgroups: sci.materials
Subject: Need to make a glass surface rough ...
Date: 26 Dec 92 22:51:13 GMT
Organization: University of New Mexico, Albuquerque


I need to make a 50 microns x 1000 microns section of glass surface
ROUGH. I have  a mask with the required dimensions. Most etchants are
"smooth", and I suspect the common HF based etchants are, too. Are there
any wet chemical etchants that can be used? 
					I also have access to RIE
and RIBE systems, but cannot think of any obvious ways to use them to
make a rough surface - so far, we have always wanted a smooth etch!
We have a full-fledged cleanroom with the usual equipment, so we should
be able to try out most  suggestions, including uncertain leads.

We are trying to make a low reflectivity strip on a mirror. This 
will be used in an external cavity configuration. Initially we thought
of making crossed diffraction gratings, but there will still be a zero
order reflection.. and grating fabrication is a little involved. Hence
we are trying to find ways to make the surface diffusive using some 
form of etching, with the dimensions decided by a mask.

Any suggestions will be helpful. Thanks!

							     swami

=======================================================================
swaminathan srinivasan
center for high tech materials
eece,university of new mexico,
albuquerque, nm 87131, usa			swami@chtm.eece.unm.edu
========================================================================
						
Newsgroups: sci.materials
From: bli@uwovax.uwo.ca
Subject: STOP HERE !!!
Organization: University of Western Ont, London
Date: Thu, 31 Dec 1992 17:13:15 GMT

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