Coating apparatus – Gas or vapor deposition – Running length work
Reexamination Certificate
1999-07-09
2001-05-15
Mills, Gregory (Department: 1763)
Coating apparatus
Gas or vapor deposition
Running length work
C438S484000, C118S729000
Reexamination Certificate
active
06231673
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a manufacturing method of a semiconductor wafer, a semiconductor manufacturing apparatus, and a semiconductor device. It especially relates to improvements in adaptability to the expansion or reduction of the scale of production at a low cost.
2. Description of the Background Art
A semiconductor wafer conventionally used in the semiconductor process is a circular wafer S
0
having a generally round plane form as shown in FIG.
41
. In the circular wafer S
0
, a matrix of many rectangular semiconductor chips are formed in a chip region
150
. As one of means for saving the cost of manufacturing a semiconductor, the diameter of the circular wafer S
0
is being increased as shown in FIG.
41
. This is based on a simple hypothesis that whether the circular wafer S
0
has a large diameter or not makes little difference in the cost of processing a single circular wafer S
0
.
The circular wafer S
0
is, as shown in
FIG. 42
, obtained by first forming a generally cylindrical semiconductor ingot
152
and then slicing it along planes perpendicular to the central axis. To increase the diameter of the circular wafer S
0
, therefore, the diameter of the semiconductor ingot
152
must be increased. Increasing the diameter of the single crystalline semiconductor ingot
152
is, however, not a ready technique so that a new developing cost is required.
In addition, with the increase in the diameter of the circular wafer S
0
, a semiconductor manufacturing apparatus
155
for manufacturing a semiconductor device using the circular wafer S
0
must be modified to the apparatus
156
suitable for a larger-diameter circular wafer S
0
, as shown in FIG.
43
. Such modification of the semiconductor manufacturing apparatus needs to be made through the entire semiconductor manufacturing process.
Especially, to uniformly process a circular wafer S
0
having a larger surface area, it is necessary to improve uniformity in density of plasma or reaction gas, which requires developments of new technologies. As a result, new introduction of a more expensive semiconductor manufacturing apparatus, i.e., larger scale of capital investments, is required.
That is, the processing cost of a single circular wafer S
0
is not the same as hypothesized but tends to rise with the increase in diameter. This results in enormous costs required for the capital investments with the increase in diameter, which cannot be covered only by a semiconductor maker.
As the number of semiconductor chips per circular wafer S
0
increases with the increase in diameter, the number of semiconductor devices supplied for markets increases. If expansion of a semiconductor chip market fails to measure up to projections, the price of a semiconductor chip will fall due to a balance between supply and demand. Consequently, it could happen that the capital investments made for the increase in the diameter of the circular wafer S
0
cannot be recovered. That is, the increase in diameter is attended with risk.
Moreover, recent development of the semiconductor manufacturing technique allows integration of an enormous number of circuit elements into a single semiconductor chip, which had been unthinkable before. This is followed by a move afoot to form a highly integrated circuit by combining various circuit components (referred to as “micro cells” or “IP (Intellectual Property)”), each composed of a plurality of circuit elements and performing a certain function.
A principal purpose of the conventional semiconductor device manufacturing technique is mass production of only a few kinds. A new “IP” age wherein an integrated circuit is formed of IPs, however, requires either flexible manufacturing system or mass production of multi kinds. In this “IP” age, even a DRAM which itself is a large scale integrated circuit is handled as a single IP. Conventional increase in the diameter of the circular wafer S
0
to make a profit has been made on the understanding of the mass production of only a few kinds, but if things continue to be the way they are under the new condition of the flexible manufacturing system, it is not easy to ensure profits.
SUMMARY OF THE INVENTION
A first aspect of the present invention is directed to a manufacturing method of a semiconductor wafer comprising the steps of: (a) forming a generally columnar semiconductor ingot; and (b) slicing the semiconductor ingot along cut surfaces parallel to the central axis thereby to obtain a plurality of strip semiconductor wafers.
Preferably, the step (b) includes the step of: (b-1) removing part of longitudinal end portions of each object obtained by slicing the semiconductor ingot.
Alternatively, the step (b) includes the steps of: (b-1) cutting out a prismatic member from the semiconductor ingot, a central axis of the prismatic member corresponding to that of the semiconductor ingot; and (b-2) slicing the prismatic member along cut surfaces parallel to a side surface of the prismatic member thereby to form the plurality of strip semiconductor wafers into identical shape.
Alternatively, the step (b) includes the steps of: (b-1) slicing the semiconductor ingot along cut surfaces parallel to a central axis thereby to obtain a plurality of plate members; and (b-2) removing longitudinal and lateral end portions of the plurality of plate members thereby to form the plurality of strip semiconductor wafers into identical shape.
A second aspect of the present invention is directed to a semiconductor manufacturing apparatus comprising: a carrier portion for carrying a strip semiconductor wafer in its longitudinal direction; and a processing portion for selectively processing a partial region of a main surface of the semiconductor wafer along the longitudinal direction.
According to a third aspect of the present invention, the semiconductor manufacturing apparatus of the second aspect further comprises: a vacuum vessel defining a vacuum chamber in an inside thereof, wherein the carrier portion is placed in the vacuum chamber, and the processing portion defines a processing chamber opposed to the partial region in communication with the vacuum chamber.
According to a fourth aspect of the present invention, in the semiconductor manufacturing apparatus of the second or third aspect, the processing portion is divided into a plurality of unit processing portions for selectively performing different kinds of processing in different positions on a partial region of the main surface of the semiconductor wafer along the longitudinal direction; and the carrier portion carries the semiconductor wafer to pass it through the plurality of unit processing portions in sequence.
A fifth aspect of the present invention is directed to a semiconductor manufacturing apparatus comprising: a supporting member for supporting a strip semiconductor wafer so that one longitudinally extending edge of the semiconductor wafer is opposed to a horizontal rotation axis; a rotatory driving portion for rotatably driving the supporting member around the rotation axis; and a coating fluid dropping portion for dropping coating fluid on the semiconductor wafer along the edge.
A sixth aspect of the present invention is directed to a semiconductor manufacturing apparatus comprising: a cylinder capable of accommodating a strip semiconductor wafer with a longitudinal direction thereof parallel to the central axis of the cylinder; a heating portion for heating the semiconductor wafer which is accommodated in the cylinder; and a gas circulating portion for circulating gas from one end to the other in a direction of the central axis in the cylinder.
According to a seventh aspect of the present invention, in the semiconductor manufacturing apparatus of the sixth aspect, the central axis is horizontal. The semiconductor manufacturing apparatus further comprises: a supporting member for, while supporting the semiconductor wafer vertically, accommodating the semiconductor wafer in the cylinder.
According to an eighth aspect of the present invention, the semiconduc
Hassanzadeh Parviz
Mills Gregory
Mitsubishi Denki & Kabushiki Kaisha
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
LandOfFree
Manufacturing method of semiconductor wafer, semiconductor... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Manufacturing method of semiconductor wafer, semiconductor..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Manufacturing method of semiconductor wafer, semiconductor... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2440316