Silicon wafers have numerous uses today, especially as we continuously grow as a technological world, but there are different types of wafers and wafer processes that fit the particular needs of specific products. For example, a double side polish wafer is very useful in situations when size is of the essence. Similarly, a dummy wafer is something often used for testing purposes. It all depends on what you’re using the wafer for. Choosing the right one will provide unique advantages you wouldn’t get from other varieties. At Wafer World, our goal is always to provide the best possible wafers for whatever your project requires. If you’re ever unsure, our experts are ready to help guide you in the right direction. So, are these polished wafers right for you? Let’s take a closer look.
Wafer polishing has become a very important part of the wafer manufacturing process as the need for wafers to be thinner than ever has increased drastically in recent years. Aside from flattening them, there are a couple of other reasons why wafers are polished.
You might initially assume that making an object flatter would automatically make it more brittle, but that’s not necessarily the case with silicon wafers. In fact, polishing can make them both stronger and more flexible. This is due to the removal of contaminants that can weaken the silicon.
Before polishing is completed, wafers will typically have some damage on the subsurface due to the complex manufacturing process, specifically from wafer grinding methods. Luckily, this can easily be taken care of through polishing. Whether the focus is on just one or both sides, the quality will drastically increase.
How exactly do these wafers differ from the rest, you ask? Typically, wafers are created with only one polished side, but as the name suggests, double side polish wafers have the process completed on both sides, making an even thinner wafer for the situations that truly demand using a minimal amount of space.
One of the more apparent advantages of double side polish wafers is the increased flatness, which is especially important when creating microelectromechanical systems such as accelerometers, magnetometers, and inertial measurement units. You will also be presented with a mirror-like finish on both sides of the wafer, completely free of any type of surface contamination. If overall quality is what you’re looking for, double side polish wafers are able to deliver.
For the most part, the manufacturing process for double side polish wafers is the same as the others, with the only significant difference being that both sides are polished. It all begins with silicon, which happens to be the second most common element in the Earth’s crust. Although abundant, silicon is not naturally available in a pure form, so a melting process must be completed to turn it into a pure silicon ingot. Next, the ingot is sliced to become what you would recognize as a wafer. Due to the delicate nature of the wafers, the polishing process is automated as to not have any human-related accidents. The main tools used are diamond liquid slurry and polishing pads. To begin, one side of the wafer is held by a vacuum and slowly brought toward a platen. This platen is covered by a polishing pad and is rotated at a fast speed. Once the wafer comes into contact with the platen, the rotation will polish it to remove any damage while simultaneously making it much thinner. With double side polish wafers, this exact process is repeated on the other side, giving you a high-quality, ultra-thin wafer that is perfect for situations when size is crucial to your product's success.
Like other wafers, double side polish wafers are created with different grades, which can be useful for various types of applications. The four main categories for wafer grades include:
If you’re looking for the highest quality wafers you can use, prime grade wafers are the way to go. While they are usually going to be more expensive than the other grades available, you truly are getting precisely what you pay for. These are made with the most care and are polished to near perfection. If your project demands the best performance, this is probably the grade you should decide to use.
Reclaim wafers are essentially wafers that have been used before and are “reclaimed” for a different purpose. The process of reclaiming is completed by using both wet and dry methods to remove impurities. The finished product will be somewhat similar to a test grade wafer, however, there is a limit on how often a wafer can be reclaimed as it slightly weakens the wafer each time.
Test grade wafers are often used for equipment testing applications because, unlike prime grade wafers, these are not created to be of extremely high quality. So, if you’re looking to use your wafers for testing purposes, a test grade wafer is probably going to be a better choice than a prime grade, as the price will be less expensive.
Similar to test grade wafers, dummy grade wafers are often used for situations that need testing, such as improving safety measures or evaluating production processes. Again, if you do not require a top-of-the-line high-quality wafer, this is going to be another excellent option for you. Choosing the right wafer grade can save you a lot of money, so seeking some professional assistance is always suggested.
Finding the right wafer can make a huge difference in your product, so if you’re ever unsure which type is right for your situation, the experts at Wafer World are here to provide our expertise. Customer satisfaction is our goal, so we always strive to provide you with the highest quality version of exactly what you need. Our silicon wafers are always carefully tested, so you can always count on your wafers to function properly at the highest level. If you need wafers, contact us today for a quote.
