A quartz boat (also known as quartz wafer carrier) is used in wafer etching process. For instance, wafers are held up by quartz boat and are brought to other chamber or furnace for further processing. This is recommended for such application as it is usually done in a high temperature environment.
Here are some facts about quartz boats
- Quartz wafer carriers can come in a variety of shapes and sizes but are essentially designed to cater wafers or substrates of 4″, 6″, 8″ and 12″ diameters.
- Why quartz material is used? Because it is popular for its durability and non-reactivity to a variety of chemistries.
- It can be used for low, medium, and high temperature process applications in both atmospheric and LPCVD horizontal furnaces.
- It is usually kept next to the furnace which can be used to hold a substrate vertically.
- Wafer or substrate on the quartz boat must be positioned in such a way that it does not come in contact with the thermocouple.
- The quartz design can help reduce particles due to quartz chips which are common to conventional and shell-shaped quartz boats which contact the paddle wings.
- Eliminating contact between the rail support bands and the paddle wings greatly reduces boat warpage that is due to long process cycles at high temperatures.
What makes a good quality quartz boat?
According to experts, a good quality quartz boat offers a number of advantages and some these are the following:
- provides no wafer pinching, chipping, micro cracking, scratching, warping or breaking
- provides no wafer rattling during the boat movement
- provides an improved process uniformity
- provides no crystal slip lines; and no bonded wafer separation problems
- can reduce particle generation
- has a longer life span – 5 or more times longer than conventional boats.
How to choose a good manufacturer?
As there are a lot of manufacturers out there who are giving the same promises, it is imperative that you know how to pick the best among the rest. This can be effectively done by establishing a set of criteria based on your unique needs. But your prospective manufacturers must satisfy the following areas:
- Certification from International Organization for Standardization
- Has a license to operate – approval from state regulation agency
- Accreditation from reputable agencies such as Better Business Bureau
- The length of time in the industry
- The number of clients (and their positive reviews)
- The charges (and if they offer discounts)