A kind of Pvd equipment
Technical field
The present invention relates to a kind of semiconductor manufacturing facility, and be particularly related to a kind of physical vapor deposition (Physical Vapor Deposition, PVD) equipment.
Background technology
In semiconductor fabrication process, the film of film mainly contains two kinds of physical vaporous deposition and chemical Vapor deposition processs.Physical vaporous deposition can be divided into two kinds of vapour deposition method (Evaporation) and sputtering methods (Sputtering) again.Wherein, vapor deposition carries out in the vapor deposition chamber, and the saturation vapour pressure that is possessed when the high temperature through vapor deposition source carries out depositing of thin film; Sputter then carries out in plasma chamber, and through ion bombardment (Bombardment) target (Target) of plasma generation, the target atom sputtering sedimentation that is bombarded out forms film to crystal column surface.Because the deposition method of sputter has the excellent step covering power; In the compact district of wafer (Dense Area) and rarefaction (Iso Area) good homogeneity is arranged all, thereby the deposition method of sputter becomes one of deposit film most common form in the semiconductor fabrication process.
In actual forming sputtering film process; With treating that sedimentary wafer is positioned on the inner wafer carrying pedestal (Pedestal) of process cavity; To treat that through wafer set collar (Clamp Ring) sedimentary wafer is fixed in the wafer carrying pedestal, and the hollow-out parts of wafer set collar just in time limits the deposition region of wafer.In other words, the wafer set collar will cover the zone between crystal round fringes place (Edge) and wafer carrying pedestal and the process cavity cover, only expose the deposition region of wafer.The material of common wafer set collar is a stainless steel.
But along with the interconnection (Interconnection) of some product and encapsulation (Packaging) demand in later stage; When aluminium liner (Aluminum Pad) film forming; The thickness of deposition of aluminum metal tunic is often greater than 20000 dusts; The process time of following is also longer relatively, causes the ion bombardment target in the plasma body and the atom that falls down also can drop on the wafer set collar.The deposition because the atom of target material drops; It is very high that the temperature of wafer set collar becomes; And the wafer temperature of wafer set collar below also can increase, and characteristic is in the crystal round fringes zone, tends to cause wafer and wafer set collar to stick together; And protruding (Whisker) defective of the coring shape of crystal column surface, wafer is impacted.
Summary of the invention
In order to overcome the problems referred to above, the present invention provides a kind of Pvd equipment, can be lowered into the temperature of wafer set collar in the membrane process, and the effective wafer that brings thus of solution and the wafer set collar coring shape convexity defective of sticking together problem and crystal column surface.
To achieve these goals, the present invention proposes a kind of Pvd equipment, comprising:
Process cavity;
The wafer carrying pedestal, it is arranged at the inner bottom of said process cavity;
The process cavity cover, its be arranged at said process cavity inner around;
The wafer set collar; It is arranged at the top of said wafer carrying pedestal; And its periphery is fixed in said process cavity cover sidewall, and said wafer set collar makes treats that the operation wafer is fixed on the said wafer carrying pedestal, and exposes the deposition region of treating the operation wafer through interior week;
Deposition ring, it is arranged at the top of said wafer set collar, and its periphery is fixed in said process cavity cover sidewall.
Further, the interior week of said deposition ring is the scarp.The angle of said scarp and horizontal plane is 0 ° to 20 °.
Further, the minimum place diameter in the interior week of said deposition ring is greater than the diameter in the interior week of said wafer set collar.
Further, the member that is formed in one of said deposition ring.
Further, said deposition ring is the titanium metal material.
Further, the upper surface of said deposition ring is a uneven surface.
Further, the inner top of said process cavity is provided with target.The vertical range of said target and said wafer set collar is greater than 50mm.The vertical range of said target and said deposition ring is greater than 30mm.
Further, said wafer carrying base bottom is provided with hoisting appliance, and said hoisting appliance is used for said wafer carrying platform is raise, and makes said wafer carrying platform be fixed in said wafer set collar bottom.
Compared with prior art; The beneficial effect of Pvd equipment of the present invention mainly shows: the top through at the wafer set collar is provided with deposition ring; The atomic deposition that prevents in the film process to drop from the sputter of target causes the temperature of wafer set collar to raise, thereby has reduced the problem of sticking together of wafer and wafer set collar on the wafer set collar; And reduced the protruding defective of coring shape on crystal round fringes surface, make wafer be deposited as the membrane process technological problems and reduce.
Description of drawings
Fig. 1 is the sectional view of Pvd equipment process cavity in the prior art;
Fig. 2 is to be the temperature variation of the Pvd equipment of Fig. 1 wafer carrying pedestal when depositing 40000 dust aluminum metal layers;
Fig. 3 is the sectional view of Pvd equipment process cavity of the present invention;
Fig. 4 is the structure figure of deposition ring of the present invention;
Fig. 5 is the fragmentary cross-sectional view of deposition ring of the present invention;
Fig. 6 is the improvement sectional view of Pvd equipment process cavity of the present invention.
Embodiment
In order to understand Pvd equipment of the present invention better, earlier the Pvd equipment structure of prior art is done description.
Fig. 1 is the sectional view of Pvd equipment process cavity in the prior art.Fig. 2 is the temperature variation of the Pvd equipment of Fig. 1 wafer carrying pedestal when depositing 40000 dust aluminum metal layers.
Please refer to Fig. 1; Be provided with target 101 at the top of process cavity 100; The bottom of process cavity 100 is provided with wafer carrying pedestal 103; Be placed with wafer 104 on the wafer carrying pedestal 103, wafer 104 is fixed on the wafer carrying pedestal 103 through the wafer set collar 102 that is fixed in process cavity 100 sidewalls.When Pvd equipment begins to deposit, plasma body (not shown) bombardment target 101, the atom sputtering on the target 101 is on the exposed region and wafer set collar 102 of wafer 104.
Please refer to Fig. 2, Fig. 2 is the temperature variation of the Pvd equipment of Fig. 1 wafer carrying pedestal when depositing 40000 dust aluminum metal layers, and transverse axis is the process time, and the longitudinal axis is a temperature.
In film-forming technology process, through setting the initial process temperature is set to wafer carrying pedestal 103, through the temperature of setting wafer carrying pedestal 103 wafer 104 is heated up, with this initial process temperature is set.And the real time temperature of wafer carrying pedestal 103, correspondence has been reacted the temperature changing trend of wafer 104 in the technological process.
When aluminium liner deposition technology, because the thickness of aluminum metal layer is very thick, often surpass 20000 dusts, the depositing operation time is longer, has deposited target 101 atoms that many sputters are dropped on the wafer set collar 102, and temperature raises.When deposition 40000 dust aluminum metal layers; The wafer carrying pedestal 103 initial temperature that are provided with are 270 ℃, but are accompanied by the increase of process time, and the temperature of wafer carrying pedestal 103 is because the transferred heat of wafer set collar 102; 290 ℃ have been elevated to; Correspondence has been reacted in the technological process, the relative temperature variation tendency of wafer 104: wafer 104 temperature in technological process constantly raises, and this temperature changing trend is that institute is undesired in the deposition process.
Below in conjunction with accompanying drawing invention is done further to describe.
Please refer to Fig. 3, Fig. 3 is the sectional view of Pvd equipment process cavity of the present invention.Be provided with target 202 at the top of process cavity 201; The bottom of process cavity 201 is provided with wafer carrying pedestal 204; Be provided with process cavity cover 203 around the process cavity 201; Be placed with wafer 205 on the wafer carrying pedestal 204, the wafer set collar 206 on process cavity cover 203 sidewalls is fixed in wafer carrying pedestal 204 to wafer 205 around the process cavity 201 through being fixed in.Interior all hollow-out parts of wafer set collar 206 expose the deposition region of wafer 205.On the sidewall of process cavity cover 203, also be provided with deposition ring 205; Deposition ring 207 is positioned at the top of wafer carrying pedestal 204; The interior week of deposition ring 207 is scarp 207a; And interior all minimum places somewhat larger in diameter of deposition ring 207 is in interior all diameters of wafer set collar 206, and promptly the hollow-out parts of deposition ring 207 is slightly larger than the hollow-out parts of set collar 206.Vertical range between target 202 and the wafer set collar 206 is greater than 50mm.The vertical range of target 202 and deposition ring 207 is greater than 30mm.
Please refer to Fig. 4, Fig. 4 is the structure figure of deposition ring of the present invention.Deposition ring 207 scarp 207a arranged in interior week, scarp 207a encloses part and is hollow-out parts 301.The material of deposition ring 207 is the titanium metal material, and titanium metal has lower thermal expansivity, and uses one-body molded manufacturing to form.The upper surface (not shown) of deposition ring 207 is a uneven surface, helps the target atom that sputter drops and is deposited on deposition ring 207 better, and can not drop to crystal column surface.
Please refer to Fig. 5, Fig. 5 is the fragmentary cross-sectional view of deposition ring of the present invention.Deposition ring 207 scarp 207a arranged in interior week; Scarp 207a is downward scarp; And scarp 207a comprises 0 ° to 20 ° with the angular range that deposition is changed the angle 207b of 207 horizontal component; Preferred angle angular range is 16 ° to 20 °, and the angle angle is relevant with the vertical range between deposition ring 207 and wafer set collar 206 (not shown)s.
In aluminium liner deposition technology, plasma bombardment target 202, the atom sputtering of target 202 drop and are deposited on deposition ring 205 and wafer 205 surfaces, rather than drop with wafer set collar 206 that wafer 205 contacts on.Therefore, the temperature of wafer set collar 206 can't raise in deposition process very soon, and is relative, also can not influence the temperature of wafer 205.
On the basis according to the Pvd equipment of the invention described above, also made following improvement.Fig. 6 is the improvement sectional view of the process cavity of Pvd equipment of the present invention.
Please refer to Fig. 6; Top at process cavity 201 ' is provided with target 202 '; The bottom of process cavity 201 ' is provided with wafer carrying pedestal 204 '; Be provided with process cavity cover 203 ' around the process cavity 201 ', be placed with wafer 205 ' on the wafer carrying pedestal 204 ', wafer 205 ' through be fixed in process cavity 201 ' all around the wafer set collar 206 ' on the process cavity cover 203 ' sidewall be fixed in wafer carrying pedestal 204 '.Interior all hollow-out parts of wafer set collar 206 ' expose the deposition region of wafer 205 '.On the sidewall of process cavity cover 203 ', also be provided with deposition ring 207 '; Deposition ring 207 ' is positioned at the top of wafer carrying pedestal 204 '; The interior week of deposition ring 207 ' is scarp 207a ', and interior all minimum places somewhat larger in diameter of deposition ring 207 ' is in interior all diameters of wafer set collar 206 '.Vertical range between target 202 and the wafer set collar 206 is greater than 50mm.The vertical range of target 202 and deposition ring 207 is greater than 30mm.Be provided with hoisting appliance 208 in wafer carrying pedestal 204 ' bottom; Carry out altitude mixture control through 208 pairs of wafer carrying pedestals 204 ' of hoisting appliance; Make the wafer 205 ' that is positioned on the wafer carrying pedestal 204 ', wafer 205 ' is fixed under the wafer set collar 206 ' more accurately.
To sum up; Pvd equipment of the present invention is provided with deposition ring through the top at the wafer set collar, and the atom that drops from target as sputter in the film process is deposited on the roughened upper surface of deposition ring well; The atomic deposition that prevents in the film process to drop from the sputter of target is on the wafer set collar; Cause the temperature of wafer set collar to raise, effectively prevented wafer set collar temperature overheating and conduct heat to wafer, thereby reduced the problem of sticking together of wafer and wafer set collar and reduced the protruding defective of coring shape on crystal round fringes surface; Make wafer be deposited as the membrane process technological problems and reduce, guaranteed the product yield.Especially in the deposition of thick aluminum metal layer, played splendid effect.
Be merely the preferred embodiments of the present invention in sum, the present invention do not played any restriction.Any person of ordinary skill in the field; In the scope that does not break away from technical scheme of the present invention; Technical scheme and technology contents to the present invention discloses are made any type of changes such as replacement or modification that are equal to; All belong to the content that does not break away from technical scheme of the present invention, still belong within protection scope of the present invention.