Method to planarize perpendicular write poles using a combination of CMP and reactive ion milling

A method of manufacturing a perpendicular write head comprising:

• forming a mill mask upon a laminate layer;
• depositing a first hark mask upon the mill mask;
• depositing a second hard mask upon the first hard mask;
• depositing a third hard mask upon the second hard mask;
• depositing a photoresist layer upon the third hard mask;
• removing the photoresist layer and the third hard mask;
• removing the second hard mask;
• milling the mill mask and the first hard mask to form a beveled main pole;
• depositing alumina on top of and around the beveled main pole to encapsulate the beveled main pole;
• polishing the deposited alumina to a level above the mill mask;
• milling the polished alumina to expose a portion of the mill mask;
• and
• removing the first hard mask and the mill mask.