A request for quotation that names a product and asks for a price will get you a price. For a glove-box spin-coating system, that answer says very little about whether the machine will run your process, because this equipment is two machines behind one name: an inert-atmosphere enclosure and a spin coater, each with its own numbers, and each behaving differently because the other is present. The questions written into the request decide whether three quotations become three answers to the same question, or three different products wearing the same name.
The product page for the glove box spin coating equipment lists what the supplier is willing to commit to: water vapour below 1 ppm, an overall leakage rate of 0.05 vol%/h, automatic pressure control at +15/-15 mbar, spin speeds of 300-8500 RPM for silicon wafers up to 4 inches, and a stated coating uniformity of +/- 3%. Those figures are a good starting point for the request, because each one raises a question about how it was produced and what it means on your substrate. The rest of this article covers what to state about your own process, what to ask about each published figure, and what to require from every bidder so the quotations can be compared honestly.
Describe your own process before you ask anyone anything
A supplier cannot size the atmosphere, the antechamber or the exhaust of a glove-box system from a product name. What the buyer states is what the answer is built on, and it is also what makes two answers comparable. Put the following in the request:
- The material system and the solvent you actually use. The solvent load is what changes the behaviour of a sealed box, and it is the first thing a serious supplier will ask about.
- Substrate size, type, whether it is rigid or flexible, and the wet and dry film thickness you are aiming for.
- Substrates per day, and whether runs are single samples or batches, because that decides the antechamber cycle and the recipe work.
- Whether recipes are developed on this machine or received from elsewhere, and what data your team needs after a run.
- Your room: the 220V / 50Hz supply the page lists, the space around the listed 1950 x 780 x 900 mm envelope, and what your building can supply that the page does not list, such as gas and exhaust.
The page describes this series as specialised equipment for the research and development of perovskite solar cells, OLED, lithium batteries, quantum dot LEDs and OPVs. If your use is production rather than research, say so in the request and ask for a written answer on what the machine can hold over a production day.
A request that carries this description forces every supplier to quote the same machine. A request that does not lets each supplier guess, and guesses arrive as three different prices that cannot honestly be compared.
Ask how the atmosphere figures were produced
The atmosphere figures are the heart of this purchase, and a bare number is not a specification. Ask in writing how the published figures were produced and what they mean in daily use.
- The page lists water vapour below 1 ppm and oxygen below 1, with no unit given for the oxygen figure. Ask for the unit, the instrument and the measurement position for both, and how often the instruments are calibrated. The page separately lists a water probe with a testing scope of 0-500 ppm, so ask which instrument verifies the sub-1 ppm figure.
- The overall leakage rate of 0.05 vol%/h: ask at what pressure it is measured, over what period, by what test method, and whether the antechamber and the 220 mm glove port rings are included in the test.
- The automatic pressure control at +15/-15 mbar: ask what gas supplies it, at what supply pressure and consumption, and how the control behaves while the gloves are being used, because pushing gloves in and out moves air and challenges the controller.
- Recovery time: after an antechamber cycle and after sustained glove work, how long the box takes to return below the published figures. The page does not give it; ask for it.
- Gas source: the page does not list the gas type, purity, supply pressure or consumption. That is a building cost and a daily operating decision, not an accessory.
Ask what the spin-coating figures mean on your substrate
The spin side of the machine is where your film is actually made, and its published numbers need the same treatment.
- The speed ranges are given for silicon wafers: 300-8500 RPM for wafers up to 4 inches and 300-6000 RPM above that. State your substrate and ask which range you will use, whether spin programs support ramps, multiple steps and holds, how many recipes can be stored, who can edit them, and whether recipes can be exported.
- The stated uniformity of +/- 3%: ask how it was measured. Which film, what thickness, how many measurement points, which instrument, on what substrate. A uniformity figure without its measurement method is a claim, not a specification; the same machine can hold +/- 3% on one film and miss it widely on another.
- The page lists the spin system's external dimensions as 400 x 400 without a unit. Confirm the figure and its unit in writing, because it decides what fits around the chuck and how the substrate is loaded.
- Chuck and dispense: the page lists neither. Ask which chuck is included, what your substrate needs, what alternatives cost and how long they take, and whether dispense is manual or automatic and how the volume is controlled. These two items are the ones most often discovered after delivery.
Ask about the place where the two machines meet
The two halves of the machine create a problem neither half has alone, and the request should name it. Spin coating inside a sealed box evaporates your solvent into the box atmosphere. The page states that the glove box removes oxygen, water and organic gases, which is exactly the duty your solvent adds to. Ask how the solvent vapour is handled: what exhaust, what filtration, and what your solvent load does to the regeneration interval and the consumable cost of the purification system. A box that holds its figures on a dry bench behaves differently with an open solvent inside it, and the honest answer is a regeneration plan sized to your solvent, not a number.
Then ask about the boundaries around it. Whether an antechamber is included or optional, what its cycle time is, and whether your substrate carrier fits through it, because the antechamber is where throughput is won or lost in daily use. The page lists a usage environment of 15-30 degrees Celsius; ask what the box does to its own interior over a working day, and whether the spin stage or chamber has temperature control, because film behaviour depends on substrate temperature. If your process needs a bake step, ask whether an oven is integrated or adjacent and how transfer between steps stays under atmosphere.
Read the page's claims as questions
The page lists a failure rate of 1% or less and a product pass rate of 99% or more without defining either. Ask what population each figure describes, over what period, measured how, and whether either applies to your film. Do not carry an undefined figure into a contract as an acceptance criterion; write your own instead and let the supplier respond to it.
The touch screen and PLC control are listed, which raises further questions: which controller it is, in what language the interface is supplied, whether recipe access has levels, and whether runs are logged. Ask what is recorded per substrate, in what format, and how the record leaves the machine. Data is not on the page; treat it as a requirement to be answered, not a feature to be assumed.
The listed 1950 x 780 x 900 mm envelope is the machine, not the space it needs. Ask for the weight, the service clearances and every connection the machine expects, and compare all of it against your door, lift and floor before the order, not after delivery.
Send the same questions to every bidder
Comparability is the point of a request for quotation. Put the questions above in one document and send it, with your process description, to every bidder. Ask each supplier to answer in writing, line by line, and only then compare prices. A cheaper quotation that answered fewer questions is not cheaper; it is a different purchase.
The same document should ask what is included in delivery and what is optional; who installs and commissions, and for how many days; what training is provided and for how many people; the spare parts list with prices, including purification media and seals; the warranty scope and what voids it; and the service response, in what language, and who answers when the machine is down in your country.
Two more questions place the machine in your future rather than only your present. If your process may later move to production coating, ask how your recipes transfer: the same supplier's slit coating equipment page describes a method that coats moving substrates, and a supplier who can describe the transfer honestly, including what does not transfer, is telling you how they quote everything else. And if this station is one step in a wider perovskite production line equipment plan, ask how it would exchange substrates and signals with the step before and after.
Write the acceptance test before you sign
Before signing, write what a good result looks like in your own terms: uniformity on your film, measured by your method, at agreed points; atmosphere returning below the published figures within a stated time after an antechamber cycle and after glove work; and a full day of your process run by your own operator without a visit from the vendor.
Ask for a trial on your own substrate with those criteria written down before the trial starts. Record the run: times, readings, film results, and everything that needed intervention. Send the record, not the summary, to the supplier. A record gets answers; a summary gets a brochure.
The questions in a request for quotation are the only part of this purchase that still costs nothing. A quotation that answers them can be compared, contracted and tested at delivery; a quotation that does not is a price attached to a machine whose definition you will finish later, at the most expensive moment. Send your process description and your questions to the PowerDe team through the contact page, and ask in writing for the answers the product page cannot give.
