1. A singulated semiconductor structure, comprising:
a molding compound;
a first conductive post in the molding compound having a first geometric shape in a top view;
a second conductive post in the molding compound having a second geometric shape in a top view, wherein the second geometric shape is different from the first geometric shape.
2. The semiconductor structure in claim 1, wherein at least one of the second conductive post is located at a non-active area of the singulated semiconductor structure.
3. The semiconductor structure in claim 2, wherein the non-active area is located at a periphery of the singulated semiconductor structure.
4. The semiconductor structure in claim 2, wherein the non-active area is located in a center portion of the singulated semiconductor structure.
5. The semiconductor structure in claim 1, wherein one of the second conductive post is located at a corner of the singulated semiconductor structure.
6. The semiconductor structure in claim 1, wherein the second geometric shape comprises an edge substantially parallel to an edge of the singulated semiconductor structure.
7. The semiconductor structure in claim 1, wherein one of the two different geometric shapes is conical in a top view.
8. The semiconductor structure in claim 1, wherein at least one of the second conductive posts is a dummy post disposed adjacent to at least one of the first conductive posts.
9. A singulated semiconductor structure, comprising:
a molding compound;
a conductive post array in the molding compound;
a conductive alignment mark in the molding compound, wherein the conductive alignment mark has a different geometric shape with a post of the conductive post array, and wherein a top surface the conductive alignment mark and a top surface of a post of the conductive post array are coplanar.
10. The singulated semiconductor structure in claim 9, wherein the geometric shape of the conductive alignment mark includes a polygon.
11. The singulated semiconductor structure in claim 9, wherein the geometric shape of the conductive alignment mark includes at least one curve and one angle less than 360 degrees.
12. The singulated semiconductor structure in claim 9, wherein the conductive alignment mark is adjacent to at least two posts in the conductive post array.
13. The singulated semiconductor structure in claim 9, wherein the conductive alignment mark has a same height with a post in the conductive post array.
14. The singulated semiconductor structure in claim 9, further comprising a second conductive alignment mark having a different geometric shape.
15. The singulated semiconductor structure in claim 9, wherein the conductive alignment mark includes more than one conductive feature.
16. The singulated semiconductor structure in claim 9, wherein the alignment mark is electrically connected to a semiconductor chip in the singulated semiconductor structure.
17. (canceled)
18. (canceled)
19. (canceled)
20. (canceled)
21. The semiconductor structure in claim 1, wherein at least one of the second conductive posts is electrically connected to a semiconductor chip in the singulated semiconductor structure.
22. The semiconductor structure in claim 1, wherein at least one of the second conductive posts is a dummy post disposed on a semiconductor chip in the singulated semiconductor structure.
23. The semiconductor structure in claim 9, wherein the conductive alignment mark is positioned at a non-active area of the singulated semiconductor structure.
24. The semiconductor structure in claim 9, wherein the conductive alignment mark comprises an edge substantially parallel to an edge of the singulated semiconductor structure.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A casting furnace comprising a controlled environment melt chamber and a mold lock chamber for transport of a mold to the controlled environment melt chamber for pouring of a liquid metal into the mold, the improvement comprising:
a rotary screw drive located externally from the casting furnace, the rotary screw drive comprising a rotary screw, a linear motion driven shaft element connected to the rotary screw, and a drive means, the linear motion driven shaft element moving linearly along the longitudinal axis of the rotary screw when the rotary screw is rotated by the drive means;
a lift shaft disposed within a lift shaft housing on a side of the mold lock chamber, the first end of the lift shaft attached to the linear motion driven shaft element, the lift shaft penetrating through a seal in the lift shaft housing;
a support arm attached near to the second end of the lift shaft, the support arm protruding into the mold lock chamber; and
a mold support structure attached to the support arm, the mold support structure providing means for seating of the mold, whereby raising or lowering of the linear motion driven shaft element causes the mold seated on the mold support structure in the mold lock chamber to be raised to the controlled environment melt chamber or lowered from the controlled environment melt chamber.
2. The casting furnace of claim 1 wherein the rotary screw drive is attached to the exterior of the controlled environment melt chamber.
3. The casting furnace of claim 1 wherein the linear motion driven shaft element is detachably connected to the lift shaft.
4. The casting furnace of claim 3 wherein the first end of the lift shaft is attached to the linear motion driven shaft element by a first and second connecting elements, the first connecting element attached to the linear motion driven shaft element and having a slot therein, and the second connecting element attached to the first end of the lift shaft and having an engaging element for insertion into the slot whereby the first end of the lift shaft is attached to the linear motion driven shaft element and detached from the linear motion driven shaft element by sliding out of the slot when the door is opened.
5. The casting furnace of claim 3 wherein the lift shaft housing is attached to a door in the mold lock chamber whereby opening the door causes the lift shaft to disconnect from the linear motion driven shaft element and the mold seated on the mold support structure protrudes from the mold lock chamber.
6. The casting furnace of claim 1 wherein the rotary screw drive comprises a planetary rotary screw drive.
7. A method of casting comprising the steps of transporting a mold to a controlled environment melt chamber via a mold lock chamber, pouring a liquid metal into the mold, and transporting the mold from the controlled environment melt chamber via the mold lock chamber, the improvement comprising the steps of:
providing a rotary screw external to the casting furnace,
providing a linear motion driven shaft element to move linearly along the longitudinal axis of the rotary screw when the rotary screw is rotated;
providing a lift shaft disposed in a lift shaft housing adjacent to the mold lock chamber;
connecting the first end of the lift shaft to the linear motion driven shaft element;
connecting the first end of a support arm near to the second end of the lift shaft, the support arm protruding into the mold lock chamber;
connecting a mold support structure to a second end of the support arm; and
rotating the rotary screw to raise or lower a mold seated on the mold support structure.
8. A casting furnace comprising a controlled environment melt chamber and a mold lock chamber for transport of a mold to the controlled environment melt chamber for pouring of a liquid metal into the mold, the improvement comprising:
a cylinder screw drive disposed external to the casting furnace, the cylinder screw drive comprising a hollow cylindrical screw having an interior threaded surface, an externally threaded 20 lift screw inserted in the cylindrical screw, the lift screw moving linearly along the longitudinal axis of the cylindrical screw when the cylindrical screw is rotated by a drive means, the lift screw extending into a lift screw housing by a suitable seal;
a support arm attached to the end of lift screw extending into the lift screw housing, the support arm protruding into the mold lock chamber; and
a mold support structure attached to the support arm, the mold support structure providing means for seating of the mold, whereby raising or lowering of the lift screw causes the mold seated on the mold support structure in the mold lock chamber to be raised to the controlled environment melt chamber or lowered from the controlled environment melt chamber.
9. The casting furnace of claim 8 wherein the cylinder screw drive is attached to the exterior of the mold lock chamber.
10. A method of casting comprising the steps of transporting a mold to a controlled environment melt chamber via a mold lock chamber, pouring a liquid metal into the mold, and transporting the mold from the controlled environment melt chamber via the mold lock chamber, the improvement comprising the steps of:
providing a hollow cylindrical screw external to the casting furnace,
providing an externally threaded lift screw in the hollow cylindrical screw, the lift screw moving linearly along the longitudinal axis of the cylindrical screw in a lift screw housing when the cylindrical screw is rotated, the lift screw housing located external to the casting furnace;
connecting the first end of a support arm to the end of the lift screw in the lift screw housing, the support arm protruding into the mold lock chamber;
connecting a mold support structure near to a second end of the support arm; and
rotating the cylindrical screw to raise or lower a mold seated on the mold support structure.
11. A casting furnace comprising a controlled environment melt chamber and a mold lock chamber for transport of a mold to the controlled environment melt chamber for pouring of a liquid metal into the mold, the improvement comprising:
a linear hydraulic actuator located externally from the casting furnace, the linear hydraulic actuator having an output shaft moving linearly along the longitudinal axis of the linear hydraulic actuator responsive to a hydraulic drive means;
a lift shaft disposed within a lift shaft housing on the side of the mold lock chamber, the first end of the lift shaft attached to the end of the output shaft, the output shaft penetrating into the lift shaft housing;
a support arm attached near to the second end of the lift shaft, the support arm protruding into the mold lock chamber; and
a mold support structure attached to the support arm, the mold support structure providing means for seating of the mold, whereby movement of the output shaft causes the mold seated on the mold support structure in the mold lock chamber to be raised to the controlled environment melt chamber or lowered from the controlled environment melt chamber.
12. The casting furnace of claim 11 wherein the linear hydraulic actuator is attached to the exterior of the controlled environment melt chamber.
13. The casting furnace of claim 11 wherein the linear hydraulic actuator is detachably connected to the lift shaft.
14. The casting furnace of claim 13 wherein the first end of the lift shaft is attached to the output shaft by a first and second connecting elements, the first connecting element attached to the output shaft and having a slot therein, and the second connecting element attached to the first end of the lift shaft and having an engaging element for insertion into the slot whereby the first end of the lift shaft is attached to the output shaft and detached from the output shaft by sliding out of the slot when the door is opened.
15. The casting furnace of claim 13 wherein the lift shaft housing is attached to a door in the mold lock chamber whereby opening the door causes the lift shaft to disconnect from the output shaft and the mold seated on the mold support structure protrudes from the mold lock chamber.
16. A method of casting comprising the steps of transporting a mold to a controlled environment melt chamber via a mold lock chamber, pouring a liquid metal into the mold, and transporting the mold from the controlled environment melt chamber via the mold lock chamber, the improvement comprising the steps of:
providing a linear hydraulic actuator external to the casting furnace, the linear hydraulic actuator having an output shaft moving linearly along the longitudinal axis of the linear hydraulic actuator responsive to a hydraulic drive means,
providing a lift shaft disposed in a lift shaft housing;
connecting the first end of the lift shaft to the end of the linear hydraulic actuator;
connecting the first end of a support arm near to the second end of the lift shaft, the support arm protruding into the mold lock chamber;
connecting a mold support structure to a second end of the support arm; and
moving the output shaft to raise or lower a mold seated on the mold support structure.
17. A casting furnace comprising:
a controlled environment melt chamber for the pouring of a molten metal into a mold;
a mold lock chamber for supplying molds to the controlled environment melt chamber;
at least one worm screw lift assembly for raising or lowering the mold through the mold lock chamber to or from the controlled environment melt chamber, respectively, each of the at least worm screw lift assembly comprising:
a rack having its length oriented with the height of the mold lock chamber;
a worm screw having teeth engaging the teeth of the rack so that rotation of the worm screw raises or lowers the worm screw in the mold lock chamber;
connecting means to connect the first end of a support arm to the worm screw; and
a mold support structure attached to the support arm, the mold support structure providing means for seating of the mold, whereby raising or lowering of the worm screw causes the mold seated on the mold support structure in the mold lock chamber to be raised to the controlled environment melt chamber or lowered from the controlled environment melt chamber.
18. The casting furnace of claim 17 wherein the connecting means comprises a rotary ball shaft wherein the worm screw is attached to the nut on the shaft, the nut rotating with rotation of the shaft and free to move along the length of the shaft, and the first end of the support arm is attached to a rotationally-independent element of the nut to move along the longitudinal length of the shaft with the worm screw without rotation about the longitudinal axis of the shaft.
19. The casting furnace of claim 18 wherein the at least one worm screw lift assembly is attached to a wall of the mold lock chamber.
20. The casting furnace of claim 18 wherein the at least one worm screw lift assembly is attached to a door in a wall of the mold lock chamber.
21. A method of casting a liquid metal into a mold comprising the steps of:
lifting the mold through a mold lock chamber to a controlled environment melt chamber by placing the mold on a mold support structure in the mold lock chamber, the mold support structure attached to a support arm;
attaching the support arm by connecting means to a worm screw so that when the worm screw rotates the teeth of the worm screw engage the teeth of a rack to raise or lower the worm screw and the mold in the mold lock chamber;
rotating the worm screw to lift the mold in position for the pour of the liquid metal into the mold in a controlled environment melt chamber; and
rotating the worm screw to lower the mold through the mold lock chamber after the pour.