Chip on board and heat sink attachment methods

A method for preventing at least a portion of a material from adhering to at least a portion of a surface of a chip scale semiconductor package, comprising:

• applying a layer of material as a mask to at least a portion of said surface of said chip scale semiconductor package, said layer including at least one of a gels a material having a filler therein and an elastomeric material;
• applying an encapsulant material to a remaining portion of said surface of said chip scale semiconductor package;
• curing said encapsulant material;
• and
• removing at least a portion of said layer of material from at least a portion of said surface of said chip scale semiconductor package.

A method for preventing at least a portion of glob top material from adhering to at least a portion of a surface of a semiconductor die, comprising:

• applying a first layer of material to said surface of said semiconductor die, said first layer of material including at least one of a gel, a material having a filler therein, and an elastomeric material;
• applying a second layer of material as a mask to a portion of a surface of said first layer of material;
• applying an encapsulant material to a remaining portion of said surface of said semiconductor die;
• curing said encapsulant material;
• and
• removing at least a portion of said first layer of material from at least a portion of said surface of said semiconductor die.

A method for preventing at least a portion of glob top material from adhering to at least a portion of a surface of a semiconductor die, comprising:

• applying a layer of material as a mask to a portion of said surface of said semiconductor die said layer including at least one of a gel, a material having a filler therein, and an elastomeric material;
• applying glob top material to a remaining portion of said surface of said semiconductor die;
• curing said glob top material;
• and
• removing at least a portion of said layer of material from at least a portion of said surface of said semiconductor die.

A method for fabricating a Chip On Board semiconductor device with a heat sink, said method comprising:

• providing a semiconductor die having a first side, a second side, and edges therebetween;
• providing a substrate;
• providing a thermally conductive heat sink member;
• attaching at least a portion of said first side of said semiconductor die to a portion of said substrate;
• covering at least a portion of said second side of said semiconductor die with a material having an exposed surface, said material including at least one of a gel, a material having a filler therein and an elastomeric material;
• applying a material to encapsulate said edges of said semiconductor die;
• maintaining said exposed surface of said material covering said at least a portion of said second side of said semiconductor die substantially unencapsulated;
• curing said material to encapsulate said edges of said semiconductor die;
• removing said material having an exposed surface covering said at least a portion of said second side of said semiconductor die;
• and
• attaching a portion of said heat sink member to at least a portion of said second side of said semiconductor die.

A method for preventing at least a portion of a glob top material from adhering to at least a portion of a surface of a semiconductor die, comprising:

• applying a layer of at least one of a material having filler therein and a gel elastomer material as a mask to a portion of said surface of said semiconductor die;
• applying glob top material to the remaining portion of said surface of said semiconductor die;
• curing said glob top material;
• and
• peeling at least a portion of said gel elastomer material from at least a portion of said surface of said semiconductor die.

A method for fabricating a Chip On Board semiconductor device having a heat sink, said method comprising:

• providing a semiconductor die having a first side, a second side, edges therebetween, and electrical terminals;
• providing a substrate having electrical connections;
• providing a thermally conductive heat sink member;
• attaching at least a portion of said first side of said semiconductor die to at least a portion of said substrate;
• connecting at least one electrical terminal of said electrical terminals of said semiconductor die to at least one electrical connection of said electrical connections of said substrate;
• covering at least a portion of said second side of said semiconductor die with a compliant protective layer having an exposed surface, said layer comprising at least one of a material having a filler therein and an elastomer;
• applying a material to encapsulate said at least one electrical terminal of said electrical terminals and at least one edge of said edges of said semiconductor die;
• maintaining at least a portion of said exposed surface of said protective layer substantially unencapsulated by said material;
• curing said material;
• removing at least a portion of said protective layer;
• and attaching a portion of said heat sink member to a portion of said second side of said semiconductor die.

A fabrication method for a semiconductor device assembly having a heat sink, said method comprising:

• providing a semiconductor die having a first side, a second side, and edges therebetween;
• providing a substrate;
• providing a thermally conductive heat sink member;
• attaching at least a portion of said first side of said semiconductor die to at least a portion of said substrate;
• covering at least a portion of said second side of said semiconductor die with a material having an exposed surface, said material comprising at least one of a material having a filler therein and an elastomeric material;
• applying a material to encapsulate at least a portion of one edge of said edges of said semiconductor die;
• maintaining said exposed surface of said material covering said at least a portion of said second side of said semiconductor die substantially unencapsulated;
• curing said material to encapsulate said at least a portion of one edge of said edges of said semiconductor die;
• removing at least a portion of said material having an exposed surface covering said at least a portion of said second side of said semiconductor die;
• and
• attaching at least a portion of said heat sink member to a portion of said second side of said semiconductor die.