Fengfan Monocrystalline silicon Solar cell Texturing Additive FP-10

Product Overview

This additive is dosed into the hot alkaline bath that textures monocrystalline silicon wafers, one of the first wet steps in a crystalline silicon cell line. In a 45% NaOH texturing bath, it steers how the caustic attacks the wafer surface, so the etch opens into a dense, even field of pyramids instead of the patchy, over-etched surface a plain caustic bath tends to give.

The pyramid field does two jobs at once. It cuts the share of light reflected straight off the front surface, and it angles the light that does enter so it travels further through the silicon before being absorbed. That is where the cell efficiency gain comes from, and it is why texture quality is judged as closely as any other step on the line.

Texturing also removes silicon. The amount taken off, the weight loss, sets both pyramid depth and how much mechanical strength the wafer has left, so the bath has to be steered rather than simply run. The additive is formulated to hold that balance, so weight loss and reflectivity stay on target from wafer to wafer and shift to shift, and the breakage rate stays low.

On the line it is handled like any other bath component: measured in at make-up, then replenished on a wafer count as production runs. No dedicated dosing system is needed beyond the pump or measuring vessel your line already uses.

Most plants qualify a new additive on one tank first. Set the recipe, run a few thousand wafers, and compare weight loss, reflectivity, breakage and final efficiency against the material already in use. Reference figures for a 460 L bath are set out in the make-up table below; your own tank size and weight-loss target will move them.

Texturing Performance

• Uniform velvet surface. The solar cell texturing additive produces an even, fine-grained velvet across the wafer rather than a blotchy finish, and the surface rinses clean without extra mechanical work.
• Consistent pyramid texture. Pyramid size and coverage stay close to each other across the wafer and from wafer to wafer, which is what keeps reflectivity readings tight.
• Adjustable weight reduction. The weight loss target can be set for the wafer format and cell design you run, and once the bath is tuned it holds that figure through the production run rather than drifting.
• Low reflectivity. Reflectivity sits at a low level and can be trimmed to the figure your process targets, and the adjusted figure stays stable as the bath ages.
• Stable cell efficiency. Efficiency holds with low fluctuation from run to run, which is what makes the additive usable as a production material instead of a trial item.
• Wide working range. It tolerates different line environments and operating conditions, so plants with different tank sizes, water supplies and shift patterns can still run the same product in the alkaline texturing bath.
• Low consumption, long bath life. Small additions go a long way, and the bath stays serviceable for a long working life, which is where the cost per wafer is won.
• Low breakage rate. Wafers come out of the texture step with few losses, protecting yield at the front of a line where every wafer is still worth full value.
• FP-10 keeps for six months in sealed storage, and the sooner it is used the better the result, because time in storage increases consumption. Store it away from direct sunlight and high heat. FP-10 does not need to be stirred before use, and leftover down additive should not be mixed with expired product.

Texture Quality Checks

Three measurements tell you whether the monocrystalline silicon texturing additive is keeping the texture step on target, and they move together: weight loss, reflectivity and pyramid appearance.

Weight loss is the simplest and fastest. Weigh a sample wafer before and after texturing; the difference is how much silicon the bath took off. It is the number that links bath strength to physical result, and it can be checked as often as the line needs without waiting for cell results.

Reflectivity is read on a spectrophotometer across the wavelength range your cell design cares about for the silicon wafer texturing step. A low figure on its own is not enough; what matters is that the figure repeats. Reflectivity that swings between cassettes shows up later as an efficiency spread that is hard to trace back to its cause.

Pyramid texture is a visual and microscope check: coverage across the wafer, uniformity from centre to edge, and any patches of untextured or over-etched surface. This is usually where a bath that has started to drift is caught, before the instrument readings move.

Set a sampling rhythm that matches your line, every cassette at start-up and then at fixed intervals, and keep the readings against bath age and replenishment history. Tracked together, the three readings let a change in caustic strength, temperature or additive dose be corrected before a whole batch of wafers is affected.

Bath Make-Up and Replenishment

Process Control Sequence

1. Clean the tank and lines, and confirm the circulation or filtration loop is running before anything is charged.
2. Fill the tank with water to the working volume for your bath.
3. Add the 45% NaOH at the make-up quantity with circulation on, and let it mix fully.
4. Heat the alkaline texturing bath to the make-up temperature and confirm it is holding steady before the additive goes in; a bath that is still climbing etches unevenly from the first cassette.
5. Add the monocrystalline silicon texturing additive at the make-up quantity while circulating, so it disperses through the bath rather than pooling near the addition point.
6. Titrate the caustic and check the temperature before the first cassette, and record both readings against the bath.
7. Start production and count wafers. Replenishment is set by wafer count, not by hours run, because consumption follows the surface area etched.
8. At each replenishment point, add caustic, then the solar cell texturing additive, then water at the rates in the make-up table, keeping circulation on throughout.
9. Review weight loss, reflectivity and cell efficiency against your targets and adjust the recipe for the next run. The make-up and replenishment figures above come from one customer's bath: tank size, wafer format and weight-loss requirement differ from plant to plant, so treat the numbers as a starting point and set your own with our technical team.

Bath Maintenance and Equipment

• Dissolved silicon. The bath takes silicon into solution as it etches, and that concentration climbs with every wafer processed. Left too long it slows the etch and coarsens the pyramid field, so track bath age by wafer count and plan the change before quality falls.
• Caustic concentration. Titrate on a fixed schedule. Consumption per wafer is not constant over the life of a bath, so a replenishment rate that suited a fresh bath will be wrong a few thousand wafers later.
• Temperature control. Etch rate follows bath temperature closely. A heater with a dependable sensor and a stable set point keeps day-to-day variation small, and a covered tank keeps loss and contamination down between shifts.
• Circulation and filtration. Keep the loop running so concentration and temperature stay even across the tank, and so particles that would cause pits are carried to the filter instead of settling on the wafers.
• Tank and wetted parts. A hot 45% NaOH texturing bath is aggressive. Confirm that the tank liner, pump seals, hoses, valves and dosing lines are rated for it before a new bath is charged, and replace any part that has been softened or discoloured.
• Dosing and records. Whether the additive is measured by hand or fed by a dosing pump, log the volume added and the wafer count behind it, so consumption per wafer can be compared between baths and between deliveries.
• Bath replacement. When replenishment can no longer hold weight loss and pyramid quality, remake the bath. A written log of wafer count per bath turns that into a planned stoppage instead of an emergency.

Storage and Handling

Keep containers sealed and store them away from direct sunlight and away from high heat. Under those conditions the sealed storage period is six months.

Use the material as close to its production date as possible. The shorter the time between production and use, the better the result in the bath; as the additive ages, consumption rises, so older stock costs more per wafer even though the drum looks the same.

There is no need to stir the product before use. It goes into the bath as supplied, measured straight from the container.

Do not mix leftover additive from a part-used container with expired product, and do not blend old and new material in the same drum. Once a container is opened, close it again after each addition and mark it with the date it was opened, so a part-used drum can be finished first.

Run first in, first out across the store. An aged drum is not free stock; what it saves on the shelf it gives back in the bath. Handle the additive according to the safety data sheet for the batch, and apply the same discipline to the caustic it is used with.

Substrate and Line Compatibility

• Monocrystalline silicon wafers. The bath is built around mono wafer texturing, and that is where the pyramid behaviour and the adjustable weight loss described above apply.
• 45% NaOH. The reference figures assume 45% caustic. If your plant buys caustic at a different strength, convert the quantity and confirm by titration rather than by volume alone.
• Incoming wafer condition. How the wafers arrive, their surface finish and prior cleaning, sets the starting point for the texture. If incoming quality changes, re-check the texture on sample wafers before changing anything in the bath.
• Post-texture rinse and cleaning. Residual alkali has to be rinsed away before the wafer moves on, and the rinse and clean that follow texturing are part of the same process window rather than a separate one. Changes there can look like a texture fault.
• Other additives. Do not blend this product with another supplier's texturing additive in the same tank without checking with us first; two additive systems in one bath make any problem impossible to trace.
• Multicrystalline and other substrates. Alkaline texturing with NaOH is a monocrystalline route. If you run multicrystalline wafers or another substrate, tell us before ordering so the chemistry can be matched to the line.

Batch Consistency

A texturing recipe is tuned to one additive, so a change in the additive shows up quickly in weight loss and reflectivity. That is why each delivery is supplied as a single production batch, with the batch number carried on the container.

Keep a retained sample from each drum before it goes into the bath. If a bath starts to behave differently, pyramids coarser, weight loss drifting, replenishment needing to be pushed harder than usual, compare the retained sample with the previous batch before touching the recipe. In most cases the cause sits elsewhere: a new caustic lot, a change in the water supply, a different wafer supplier, or a bath further into its life than the log suggests.

When you report a problem, quote the batch number and the make-up date. Those two pieces of information let the material be traced back through production, so a question about the additive gets answered rather than guessed at, and the line is not held up while the cause is searched for.

Related Products

Ordering and Delivery

• Payment. 100% T/T in advance.
• Minimum order quantity. Varies by chemical; confirmed with our sales team per order.
• Lead time. 2 weeks.
• Packing. 10 kg/box; 25 kg or 50 kg/bag; 20 kg/25 kg/30 kg/200 kg/drum; 1000 kg/IBC drum.
• Shipping. Per the terms agreed in the current contract.
• Samples. Ask your sales contact about sample availability and the quantity you need to run a trial on your own tank.

Compliance & Documentation

Bulk & Project Supply

A texturing bath is charged once and then fed wafer by wafer, so the volume a plant needs over a year is set by three figures: how many tanks you run, the working volume of each, and the wafer count behind every replenishment. Send us those numbers together with your wafer format and weight-loss target, and we will build a supply plan around them rather than quoting a single pack.

Qualifying before committing volume. Most cell lines run the first drums through one tank, hold it through a full bath life and compare weight loss and reflectivity against the additive already in use. Once those figures repeat, the same grade is released to the remaining tanks. Rolling out tank by tank keeps the risk on one line and gives a clean before-and-after comparison.

One grade across repeat shipments. A recipe tuned to one grade should not have to be re-tuned every quarter. Repeat orders are supplied as the same product grade with the same reference make-up figures, so a bath that was set up on the first delivery can be rebuilt on the next one without changing the process window.

Campaign planning. Where a plant schedules texture campaigns around cell line maintenance or seasonal output, share the production calendar. Deliveries can then be phased so drums arrive before a bath change instead of sitting in store, which matters because consumption rises as the additive ages.

Buffer stock for multi-tank plants. Plants running several texturing tanks at once usually keep one bath charge in reserve so a tank can be remade without stopping the line. Tell us the reserve volume you want to hold and we will include it in the supply plan.

Distributors and regional stock. Importers and distributors who carry this solar cell texturing additive for several cell plants can order against a rolling forecast instead of one-off lots, keeping a single grade in stock across their region and matching deliveries to the customers they supply.

What travels with a bulk lot. Every consignment carries its batch number on the container, so a bulk delivery can be booked into stores and released to production without a separate paperwork chase. Where a project needs declarations for material qualification, raise it when the volume is agreed.

Technical Support & Model Matching

Choosing the right match is where most sourcing decisions stall. As a trading supplier, we keep one point of contact from first enquiry to after-sales: tell us what you are making and the conditions you work under, and we shortlist the closest matches from our supplier network, compare specifications and arrange samples before you commit to a bulk order. If something does not behave as expected, we work with the supplying partner on the cause and a practical fix, and stay with the case until it is settled. Email, WeChat or WhatsApp enquiries get a reply within 24 hours.

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