Assertion: circuit board's layer | /r/HasProperty | formed
Facets:
value: previously
type: TEMPORAL
Source sentences:
text: Although both first layer 3 and second layer 4 can be baked by raising the temperature to 400° C. during their formation, using the above-mentioned procedure saves time, and it also has the advantage of not subjecting the layer beneath these layers, which have been previously formed, to unnecessary thermal stress.