Thin Film Deposition - Science topic

I am not able to understand the reason behind non-stoichiometric behavior shown by the thin films deposited with reactive sputter deposition technique.

It’s similar to what you would see when looking at a shallow puddle of water with oil on top. Here is an example of a Airbus cockpit window with the same rainbow effect:

Thin-film interference is a natural phenomenon in which light waves reflected by the upper and lower boundaries of a thin film interfere with one another, either enhancing or reducing the reflected light.

It's the same mechanism behind your oil example. The thin film in this case is the heating coating applied to the windshield, which is intentionally non-uniform (explained below), making the effect even stronger.

Fringes observed on a windshield due to thin film interference caused by a conductive Indium Tin Oxide (ITO) thin film deposited on the window for electrical defrosting/defogging.

The fringes are strongly visible because the thin film thickness is highly non-uniform on purpose: as the voltage is applied on two opposite points of the window, a uniform conductive film (uniform sheet resistance) would lead to non-uniform current density, and non-uniform defrosting. Some window parts, especially on the sides and far from the electrical contacts, would dissipate less heat, and defrosting would be significantly less efficient here. The ITO thickness pattern is cleverly designed to provide a rather uniform heat dissipation over the whole window.

- Thermal Deposition

- DC-magnetron sputtering

- Vacuum evaporation

- Sol-gel method

- Chemical vapor deposition

- Electron beam evaporation

- Spray pyrolysis

According to Figure (windshield), a non-uniform thickness of the deposition layer is applied to the windshields of the windshield aircraft.

I want to deposit MoO3 over ITO by spin coating, but I am looking for some  transparent binder which can prevent dissolving the MoO3 thin film in 1M H2SO4 electrolyte in electrochemical analysis.

I have tried different standard methods of Si wafer cleaning like RCA1, RCA2 and ultrasonication with acetone and IPA, but it didn't work out well. I have observed the wafer surface before and after cleaning with an optical microscope. The surface is almost similar in both cases.

I attached the silicon surface images obtained from an optical microscope for your reference.

Can anybody please help me to get a clean Si surface for the deposition of thin films ( around 100 nm) using sputter deposition?

Dear all, I am going to fabricate thin film of a perovskite material using Pulsed Laser Deposition. In bulk form, we can easily measure the electrical properties such as dielctric constant, Polarsiation etc. by simply coating the bulk pellet with Ag/Au. I am wondering how can I do the same if want to do same characterization of a thin film deposited over a substrate(say Si/SiO2).

Some researchers explain the development of preferred orientation texture during growth of thin films deposited using PVD sputtering techniques as a competition between strain and surface energy. For example in CrN films, the (200) plane is the lowest surface energy plane; whereas the (111) orientation of CrN would be expected when the strain energy predominated. How's the surface energy of this plane is determined? And there's any relation with the surface energy of thin films calculated using Owens, Wendt, Rabel & Kälble (OWRK) method with contact angles?

Thanks in advance.

I do Ti/Au e-beam deposition on bi layer PMMA and Az1505. there is bubble like deffect that is forming on the substrate. the starting pressure is around 2-4x10 -7 T and climb to 2x10 -6 T during deposition. I don't have temp reading. deposition rate is 4 A/s. i do 2x300 nm with a 15 min pause. what could be the source of the problem? i did a lot of that kind of deposition in the past with no problem. the only difference is that we change the cryopump in early january. any hint will be appreciate.

I am working on depositing thin film of Silver on Quartz by DC Magnetron Sputtering. What would be the best way to clean quartz substrate ?

I am trying to deposit a thin film of ferrite on a platinum coated silicon substrate by a dip coating method. But when the substrate is being pulled out of the solution, whole deposited layer drained from the surface of the substrate. So how can I increase the adhesiveness of thin film on a substrate? or the wettability of platinum coated silicon substrate for thin film deposition?

I am trying to investigate the conduction mechanism in BiFeO3 thin films deposited on ITO coated glass substrate with Ti as top electrode. What value of Richardson's constant should i use to fit the calculated and experimental data.

Thank you in advance

To obtain the same amount of plasma at the same pressure:

Is RF power needed for (copper bonded sputtering target) is greater or equal to RF Power needed for (unbonded sputtering targets)?

For photoelectrochemical applications.

Don't know, is anyone asking for this or the same question, but

I want to do the electrochemical measurements of thin film deposited on a silicon substrate (the structure in the picture). So, should I create an insulating mask (I can get it by SiO2 (thermal oxidation) or by chemical-resistant varnish) around this film to eliminate the influence of silicon surface on measurements?

trying to find out hydrogen concentration in a thin film deposited on glass.

How does the argon flow rate affect the crystalline quality of TiO2 anatase thin film deposited at constant temperature (350 °) in the sputtering method (other deposition parameters are also constant, varying only the flow rate of Ar )?

I'm looking for a rubber-like material with low permeation to water vapor. Rubber itself doesn't work for my application because it is very permeable to water vapor. Thanks.

I am looking for a lab where I can coat some films with metal oxide and/or metal oxynitride using plasma-activated thin film deposition equipment, preferably roll-to-roll. Thanks!

I am using carbon/silver paste as adhesive for thin film deposition. After that, I want to remove the paste residue. It seems acetone + methanol + IPA does not work.Attempt to try piranha solution.

Hello, I will try to produce Sb2S3 films with thermal evaporation technique using Sb2S3 pellets or Sb pieces. Then I will complete the production with thermal annealing. Could you please give information about the risks of Sb2S3 pellets or Sb pieces and the precautions I should take?

Please explain in details

I aim to deposit Sno2 thin film on ITO substrate using spray pyrolysis. What are the vital points I should take into consideration?

Are there interlayer materials like TaN for copper nano film deposition, so that copper doesn't diffuse into a silicon wafer, are there any such materials for tungsten deposition?

I am facing lift-off issues (resist gets hardened) for Tungsten deposited by e-beam evaporation and sputtering and no patterning is obtained. What is an effective way to deposit Tungsten? 

My query is whether the helium plasma can etch the surface of deposited film and damage the film more in comparison to hydrogen plasma?

The gap between my plasma zone and substrate at present is ~50mm. If the previous damage is imminent, can increasing the gap between plasma zone and substrate is a good solution?

Kindly suggest.

Hello all,

My goal is to achieve a perovskite (cs lead bromide) film with high stabiity under humid environment? What is the standard ay I can check the PL stability of the films deposited?

a group of theoretical researchers want to develop a metal oxide thin film at low temperature which growth techniques would you use to realize the film? and why?

The above illustrated question is mismatching with my thinking, Is it means growth modes of thin Film or methods used to deposit a film in nano scale at low temperature?

, Thanks

Hi,

I'm doing a process that uses a thin layer of SU-8 as an insulator. I was getting short circuits so I made a simple metal-SU8-metal structure (Figure 1 ). My SU-8 tests included SU8-2000.5, 2001, and 2002 with thickness varying from 0.7 um to 4.5 um. I also tested two different e-beam evaporated thin films, gold and chromium, around 100 nm for each layer.

All of them seemed to be shorted. I have attached some pictures showing the layers under the microscope (Figure 2-5). I spotted some potential pinholes or bubbles ONLY in SU-8 layers on top of the bottom electrode. The SU-8 layer alone on Si and Au/Cr layers alone seem rather clean. I wonder why this is happening and if you have any suggestions?

Hello,

I have a question regarding statistical analysis of the thickness of thermally evaporated organic thin films. I need to deposit a rather thick organic film (300 nm) through a slow thermal evaporation process. After a few repetitions, it becomes clear that there is always a mismatch between the target thickness and the measured thickness, and the deviation had a normal distribution. In order to estimate the standard deviation of the thickness and run capability analysis, I needed to have a large sample size of these deposited films. In the interest of saving time and material, I have done my repeated qualification runs at a smaller target thickness of 50 nm. While I now have the mean and standard deviation of the process with a target thickness of 50 nm, I'm wondering how to derive the corresponding data for a target thickness of 300 nm. I assume I can simply multiply the mean by 6. But how about standard deviation? Can I simply scale that linearly as well?

Thanks,

Pouyan

Dear all,

I am currently working on BTO thin films deposited on Si/SiO2/TiO2/Pt substrates via chemical solution deposition (Sol-gel + spin coating).

How can I leave some part of the bottom electrode uncovered during the spin-coating?

I have tried with the tape method but it´s not always successful, is there another way?

Thank you for the help.

Regards,

Federica

I need to disperse Fe304 nanoparticles (25nm) in PVA solution. I tried to do it using a bath sonicator as well as a probe sonicator but the particles seem to agglomerate and settle down at the bottom.

So, I decided to coat the particles with a surfactant and then disperse them, below is the steps I followed for coating:

Step 1: 0.05g Fe304 NMP were added to 2ml of citric acid(0.5g/ml conc) and were left to incubate at 90C for one hour

Step 2: After one hour, the solution was subjected to vigorous stirring for one hour while maintaining the temp at 90C.

Step 3: The black precipitate was washed with deionized water and centrifuged 3 times to remove any remaining citric acid.

Step 4: The particles obtained from centrifugation were dried at 100C to remove any water.

After the above procedure, I tried to check if the coat was successful by seeing if the particles were attracted to a magnet and they were, so the problem of dispersion remains.

Did I miss out a step in the coating process? Can I use another method to successfully disperse the NMP.

I have fabricated the ZnO thin film on glass substrate. I have found only the (100) and (101) planes in XRD of ZnO thin film. 

I am attempting to prepare GO paper using the vacuum filtration technique, I used a cellulose acetate membrane to filter the GO solution(1mg/ml) andwas able to get a brown film on the membrane, the membrane was dried it at rtp initially and then put it in the oven at 50C for 12h, however the thin GO film remained attached to the membrane rather tightly.

Lit. mentions that the film can be easily peeled off the membrane however in my case I am not able to peel it  at all. Can anyone with experience in this suggest how it can peeled off?

I tried to dissolve the membrane by dipping it in acetone and the membrane did dissolved within seconds leaving behind only the thin GO film like I wanted, but the problem is the GO film got wrinkled and isnt smooth anymore. (Pic attached).

Any suggesting on removing the film while maintaining its smoothness are welcome.

P.S.- I know other membranes might give better results but unfortunately I only have a cellulose acetate membrane and need to do it using this.

Few days back, I deposited Zn film on glass using e-beam evaporation and it was successfully deposited. The vaccum was about 3x10^-6 mbar with diffusion pump. Today, when I turn on the system I could not get high vaccum. The penning gauge is not responding and it stuck to ^-3 mbar. All appears to be okay, I just could not figure out the problem. You suggestions are highly appreciate.

Hi all,

I deposit Sb2Te3 thin film 150nm by PVD (sputtering, single target, with low power as much as I can) on SiO2 substrate and anneal it to 200°C with 0.5K/min as rate.

I found some sample got damage and ashes around the films.

I would like to have comments from this issues.

Keep healthy,

Best

Could anyone provide names of metal thin film deposition vendors that also do high temperature annealing, in the range of 300-500 C?

I need a simple cleaning procedures

Hello all, I have used E-beam evaporation to deposit the Ti-Ni film. However, the composition of the obtained film (Ti:Ni~1:8) is far away from the corresponding ingot (Ti:Ni=1:1). The ingot was prepared by arc melting, for homogeneous element distribution.

Currently, I'm about to prepare some equiatomic TiAlV films by EBPVD. To this end, I may need to deviate the ingot composition slightly from 1:1:1. Can anyone suggest a potential solution? Or is there any theory that can help me design the ingot composition so that I can obtain near equiatomic TiAlV films? Best.

I want to measure the contact resistance of metal oxides thin films deposited on top of n-type silicon wafers. Can I use the Transfer length method for measuring the same?

Hello all,

I have to do RF sputtering for MoO3 for my LED project. But I have come across many recipes for reactive RF sputtering of MoO3 ,using Mo as a target and Oxygen as the reactive gas But I want to RF sputter MoO3 directly (not via Mo target and then react it with Oxygen). Can anyone suggest me a good recipe for that?

Thank you being helpful with my other questions.

Optical emission spectroscopy for plasma diagnostics of low temperature plasma

Hello,

I am making a graphene oxide/polymer composite membrane using spin-coating. When the precursor solution is made (blending and sonication of polymer with graphene oxide, followed by centrifugation), I get a clear solution that is stable for over a week. However, when spin-coated, the graphene oxide agglomerates, and I end up with poor membrane performance. I tried different spin coating techniques, precursor solution ratios, and many other ways but I seem to face the same problem. Any idea what is causing this?

I am depositing Al onto PMMA via thermal evaporation. Currently I have already tried to improve the adhesion of the films by two different strategies:

1. Evaporating SiO prior to the Al deposition i.e PMMA+SiOx+Al

2. Introducing/eliminating air plasma etching performed before the evaporation of Al or SiO+Al mixture

I can't achieve proper adhesion of the Al films. The Al films totally delaminate after tape test no matter which combination of the two listed strategies I use. Does anyone have any experience with this kind of thermal evaporations? Any reccomendation about other adhesive layer alternatives beside SiO with high adhesion on PMMA?

How to measure the Seebeck coefficient and the thermal conductivity of thin films deposited on the ITO substrate. the thicknesses of the thin films are between 200 and 500 nm.

I was wondering if increasing the bias voltage during deposition of DLC coating would increase the carbon content as well. Any papers pointing to the relation between bias voltage and increasing the carbon content in diamond like carbon coatings/films.

Adhesion is of vital interest in thin-film science because the fragile film relies on the underlying substrate, and the adhesion between the two for durability.

my question is:

Is there an easy method to calculate the adhesion ratio of thin film deposition by spray pyrolysis method to substrate?

Adhesion is of vital interest in thin-film science because the fragile film relies on the underlying substrate, and the adhesion between the two for durability.

my question is:

How to change the adhesion ratio of thin film deposition by spray pyrolysis method to substrate with the change of the substrate temperature?

Dear all:

Have anyone deposited Al contacts on substrates of CdS and/or PbS, using an e-beam physical evaporation system ?

The following is happening with my CdS and PbS films ,

I'm trying to deposit a good quality Aluminum electric contacts with an e-beam evaporator, on the top of chemical bath deposited CdS and PbS thin films...

In both cases I'm trying to grow a deposit of 200 nm or 300 nm of Al. But when I run the deposits on the CdS films, the Al deposited above de CdS looks with a 'regular' quality, however sometimes I get a silvery uniform finish of the contacts.

But when I try to do the same on the PbS thin films, I always finish with a deposits with a somewhat white aspect, meaning that Al₂O₃ is growing on there, but this doesn't happen with the CdS films ...

Anyone has experimented something like it ?

Do you think the roughness of the films may be having an impact on whether pure-Al or a mix of Al and Al₂O₃ is growing on the e-beam deposited films ?

I am doing both deposits (Al on CdS and Al on PbS) with exactly the same conditions (i.e. current, grow rate, temperature and vacuum pressure).

Do you think it could be a matter of the surface of the susbtrate ? .. this would be unexpected, since I am growing 300 nm of Al... is not 10 nm, so the substrate should n't have an impact on the morphology of the above deposited thin film, and not to say an impact on the chemical composition of the surface of the films (Al films).

I hope someone can give me any help

Kind Regards !

How to change the optical properties of tin oxide thin films deposited by spray pyrolysisthe by changing the solution concentration?

Dear all:

I am looking for the data of the Vapor Pressure for these substances :

- Bismuth

- Tellurium

(for both of these elements I found a few data, but for points of temperature above 650 °C)

- And Bi2Te3;

after have searched for the Vapor Pressure of Bi2Te3 in literature, I found any data, as if the Vapor Pressure for Bi2Te3 coudn't be possible to be measured.

Does anyone know why is this ?

Or, Is it that I need to search for longer ?

Even in some data sheets there is a empty space for the Bi2Te3's Vapor Pressure.

Hope someone can help me with this.

Thank You !

Regards, !

Hi All ,

I am using a fresh Silicon target (dia 2 inch and 6mm thickness 99.99%pure ). The base pressure of the system before gas flow is 10^-5 mbar and the Ar mass flow sccm value is set to 20. Then the pressure is 10^-3mbar. The power is given 20W. The reflected power is 0W. The target-substrate distance is 6 cm. The system is rf magnetron sputtering with has a automatic matching network. The plasma is pinkish purple. I have done this for 1hr still there is no silicon deposited on glass substrate.

I am not able to find the reason for no coating. Please help.

Thanks,

Sutapa

Please is there any simulation software for thin film deposition and characterisation? If there, how and where can I get it?

I have tried at 25 mTorr Ar, 50-75 watt with commercially bought porous Si target. But I have not got any deposition. I have not found any reason for this failure also.

Dear all :

I need help with the following question :

It is possible to grow n-type Bi2Te3 thin films, deposited on glass substrates using the e-beam technique ? If so, What would I require ? or What considerations do a have to take ?

I have acces to an e-beam deposition chamber and I have Intermetallic crucibles (BN-TiB2) and Graphite crucibles.

Then, I have a commercial bulk-Bi2Te3 n-type. So, my plan is to cut a piece of the ingot, and then breake pieces into little pellets, to place them directly into the crucible ,

Will this work ?

Thank you for the help ! :)

Regards !

I am trying to simulate the deposition of Silicon over SiO2. In reality, when we try to deposit a crystalline Silicon over SiO2 (amorphous), we get rather a polycrystalline Silicon. In ATHENA though, when simulating the same process, the final deposited Silicon layer is not Polycrystalline Silicon but Crystalline silicon.

So, If someone can help me know how to capture this effect in Silicon and how to measure the quality of the deposited film in the Silvaco ATHENA TCAD tool, it would be really helpful.

If the proper simulation is not possible in ATHENA, please let me know which tool can capture these effects properly.

I have some powder samples. For photoelectrochemical measurement (PEC) measurements, I want to prepare thin film of my samples on FTO. Can any one please help me which Nafion solution I will use for it? As there are different type of Nafion solution are available in Sigma Aldrich and Alfa Aesar.

Hello RG fellows, I am trying to coat/deposit a thin layer via PECVD on Polypropylene substrate. The functionality of the coating will be water-vapor barrier. Which precursors are the best for this purpose? Thanks!

I am trying to coat pure silicon on a glass (and SiO2) substrate with a sputtering machine. But I obtain the SiO layer instead of Si each time! Our initial pressure is 3E-7 Torr and pure Ar gas (%99.999) is used during the sputtering procedure. We use about 50W power for sputter gun.

Does anybody know the problem?

Dear colleagues:

When you have an Aluminum plate, and then, lets say you sand its surface with a sandpaper, you remove its native Al₂O₃ thin layer previously formed on the surface.

Instantly, after you remove it ,the Al₂O₃ quickly grow again, due to the exposure to the Oxygen on the room environment.

Does anyone know What is the Growth Rate of this thin film ? and, What is roughly the film's thickness achieved by this process at a regular room atmosphere?

Thanks all !

Hi,

I am currently struggling to achieve a uniform thin film coating of Zinc oxide nano particles for use in QD-LED device.

I have many papers detailing similar steps towards achieving the above but I have not been able to.

I made 40mg/ml solution of ZnO NPs dispersed in a 1:2 (IPA:MeOH) solvent and toluene. Attached is an image of the IPA:MeOH mix (1500rpm for 30seconds).

The toluene samples appeared to create a better film with less aggregation but still not satisfactory.

I have varied the speed settings from 1000rpm to 5000rpm, time from 30 seconds to 2mins and the quantity of ink used from 100ul to 500ul without thin film being achieved.

Annealing makes not noticeable difference to the final product.

I am about to test dispersing the ZnO NPs in PMMA to see how this fares.

Would any be able to provide any feedback on the steps I have taken so far if there is anything noticeable that I am missing to achieve thin film?

I have read though the FAQ section of the ossila website for how to counter the streaking defects I am experiencing but with no luck.

Must I employ a purification step or specific dispersion technique when making my solutions for deposition?

Thank you.

I am measuring the resistance of a CNT thin film deposited on Si substrate with a four probe attachment setup. The setup consist of a nanovoltmeter and current source with copper probes. The I-V curve in a direct DC sweep measurement is in the figure. I was hoping if anyone may have an explanation for such a behavior or guide me into the potential measurement errors from the described setup (Such as effect of substrate, probes, etc) that may have caused this.

Can we have a easy approach of using a different material other than Pt in DSSC without compromising the performance of DSSC

Hello, I would like to ask the possibility of failure piezo properties performance of AlN thin film deposited by reactive sputtering? I have good ellipsometry, XRD & SEM results but poor piezo- coefficient. The only thing I thought there is 3-4% Oxygen in EDS results. Thanks for advise.

Which equipment can be used to measure this?

How can I calculate the measurement?

Based of my research I found it high N2/Ar ratio with deposition pressure give me a well C-axis oriented sample, however as we know the target became poison and there are defects on AlN due to high N2 gas.

What would be the good parameters to deposit AlN layer to avoid poisoning as well as get good c-axis orientation? I use high N2 ratio, 300-400 C heat subs before and during deposition and low deposition pressure about 2-4 mTorr.

My goal is to get very well C-axis oriented film with narrow FWHM rocking curve.

I use DC reactive sputtering without bias voltage and never used RF sputtering.

Thank you

Saeedeh

I am working on semiconductor thin films. When I recorded transmittance spectra of thin films deposited at different thicknesses, for some films i got interference patterns and for some films i didn't get interference patterns in the spectra. What is the reason?

I'm using a home-made PECVD processing chamber with parallel plate/showerhead reactor. I may add reactive and carrier gases as needed, but I don't know details about feeding hexamethyldisilazane (HMDSN) as precursor. Any information would be greatly appreciated. Thanks.

I deposited Zinc thin films on two types of substrate materials, one is ITO and second quartz substrate. When I calculated optical direct band gap there is difference in energy for 0.2-0.4 eV higher for Quartz.

Is there any reason why I am getting higher band gap for thin films deposited on quartz than on ITO?

I am doing theoretical research on thin films and want to know the procedure of simulating thin films deposition and growth using NASCAM interface.

We observed a dye absorption blue shifted when deposited as a thin film from a solution. Also the spectra is broadened for film.

Any clarifications.

We performed the concentration dependent solution study and we dont see such peak shift and broadening. This is happening only in thin film. the thin film is deposited on glass substrate using the spin coating technique.

Repeatedly, I am getting a peak at around 26.5 (2 theta) in thin film sample (either impure phase or wurtzite structure) while I have changed most of the possible parameters in sputtering as well as heat treatment (300 to 575 degree C at different S vapor)