Correction of fabricated shapes in additive manufacturing using initial layer

A method of fabricating a polishing pad using an additive manufacturing system, the method comprising:

• receiving data indicative of a desired shape of the polishing pad to be fabricated by droplet ejection by the additive manufacturing system, the desired shape defining a desired profile including a polishing surface having a plurality of partitions having substantially flat top surfaces and separated by one or more grooves on the polishing pad;
• generating data indicative of distortions from the desired profile caused by dispensing of a plurality of layers by droplet ejection by the additive manufacturing system, the distortions including variance from the substantially flat top surfaces of the plurality of partitions;
• generating data indicative of an initial layer to dispense by droplet ejection to at least partially compensate for the distortions of the substantially flat top surfaces of the partitions from the desired profile, the initial layer extending across less than all of a width of at least one partition of the plurality of partitions;
• dispensing the initial layer on a support by droplet ejection, the initial layer providing a portion of the polishing pad;
• and
• dispensing a plurality of overlying layers on the initial layer by droplet ejection by the additive manufacturing system to form the partitions of the polishing pad, the plurality of overlying layers each extending across an entire width of each particular partition of the plurality of partitions.