While we heared of the word "standard", we think of a base principle to judge other similiar items. For instance, a three-person sofa "standard" width is 84inches. While we are refering to the word "standard" there are some important requirements on functions which are essentials.
Now let's get back to PCB. The thickness of a circuit board is a very important parameter, so even without any single "official standard", there is also some universal thickness used widely in PCB designers. In some of the circumstances, your contract manufacturer may ask you to follow some rules in order to reduce PCB manufacturing cost or to minimize the lead time. Therefore, we should see what are the popular choices on PCB thickness and then to discuss what do consider when you temped to use non-standard thickness.
What is the PCB standard thickness?
Many PCB manufacturers will say it is 1.57mm or 0.062inches. Obviously this is the thickness of bakelite substrate which are used in PCB manufacturing long time ago, and since this thickness is fixed, so we can regard this one as the standard PCB thickness of history. Yet today, PCB thickness can be more or less of it, but 1.57mm(1.6mm) is still top 1 choice among PCB designers.
Let's some other popular choices about PCB thickness
0.031 inches (0.78mm)
0.062 inches (1.57mm)
0.093 inches (2.36mm)
What factors you should consider when decide PCB thickness
What factors does manufacturers consider when consider thickness
panel to unit method
What if I want to customize my PCB thickness?
First you should know any customize on PCB thickness may lead to longer manufacturing circle. Also if your manufacturer never worry about sales and order, your irregular choice of thickness will lead to immediate rejection of manufacturing. Despite of this, PCB manufacturer may be limited to their equipment and material in stock, not to mention the manufacturing cost will rise up in large pencent.
So let's review of today: it is better to follow standard thickness, but while if you want to customize it, it will leads to longer lead time, expensive cost of manufacturing or unavailablity in your supplier of boards.