Method and apparatus for dicing semiconductor wafers
AssigneeMicron Technology, Inc.
InventorsAlan G. Wood, Warren M. Farnworth, Salman Akram
Life of this patent
Estimating the term…
Abstract
A method and apparatus for dicing semiconductor wafers is provided. The method comprises: forming an etch mask on the wafer, and then etching the wafer with a wet etchant, such as KOH, to form a peripheral groove around each die. Etching the wafer can be from the front side of the wafer, from the back side of the wafer or with partial etches from both sides. The etch process can be performed on a single wafer using a spray head apparatus or on batches of wafers using a recirculating dip tank apparatus.
Claims25
A method for dicing a semiconductor wafer comprising a plurality of semiconductor dice, said method comprising:
- forming a first mask on a front side of the wafer, the first mask comprising a first layer covering and protecting the dice;
- forming a second mask on a back side of the wafer, second mask comprising a second layer having a pattern of etch openings to the back side;
- and
- following forming of the first mask and the second mask, etching the wafer through the etch openings using a wet etchant to form a peripheral groove around each of the dice, the groove extending from the back side to the front side of the wafer and the first mask providing an etch stop and protecting the dice during the etching step.
A method for dicing a semiconductor wafer comprising a plurality of semiconductor dice, said method comprising:
- forming a protective mask on a first side of the wafer, the protective mask comprising a blanket deposited layer covering the dice;
- forming an etch mask on a second side of the wafer, the etch mask including a pattern of etch openings to the second side;
- etching the wafer through the etch openings to the protective mask to form a peripheral groove around each die extending from the second side to the first side of the wafer, with the protective mask providing an etch stop and a support structure for the dice during the etching step;
- and
- stripping the etch mask and the protective mask to separate the dice.
A method for dicing a semiconductor wafer comprising a plurality of semiconductor dice, said method comprising:
- forming a protective mask on a front side of the wafer, the protective mask comprising a blanket deposited layer covering the dice;
- forming an etch mask on a back side of the wafer, the etch mask including a pattern of etch openings to the back side;
- placing the front side of the wafer on a supporting substrate;
- with the wafer on the supporting substrate, etching the wafer through the etch openings by spraying or dipping in a wet etchant to form a peripheral groove around each die extending from the back side to the front side of the wafer, the protective mask providing an etch stop and protecting the dice during the etching step;
- removing the wafer from the supporting substrate with the protective mask supporting the dice;
- stripping the etch mask and placing the back side of the wafer on a second supporting substrate;
- and
- stripping the protective mask to separate the dice while the dice remain supported by the second supporting substrate.
A method for dicing a semiconductor wafer comprising a plurality of semiconductor dice, said method comprising:
- forming a first etch mask on a first side of the wafer, the first etch mask comprising a layer covering the dice and having a first pattern of etch openings;
- forming a second etch mask on a second side of the wafer, the second etch mask comprising a second pattern of etch openings;
- etching the wafer through the first pattern of etch openings to form a pattern of grooves extending partially through a thickness of the wafer;
- following etching, removing the first etch mask and forming a protective layer on the first side of the wafer covering the dice;
- following forming of the protective layer, attaching the first side of the wafer with the protective layer thereon to a supporting substrate;
- following attaching, etching the wafer through the second pattern of etch openings to extend the pattern of grooves completely through the thickness of the wafer;
- and
- stripping the first and the second etch mask to separate the dice.
Dependencies are inferred from the claim text.