CN205335232U - Wafer carrier - Google Patents

Abstract

The utility model relates to a wafer carrier. This wafer carrier structure is for to be used together with the chemical vapor deposition device, and this wafer carrier includes: body, this body have the top surface and the basal surface of mutual disposition each other, a plurality of depressions, a plurality of depressions are injectd wafer carrier in the surface of top, this wafer carrier's improvement includes by 14 a plurality of depressions that the depression is constituteed altogether, and every depression arranges along a circle in two circles, wherein these two circles each other concentric and with by the circular profile that the periphery formed on top surface is concentric.

Description

Chip carrier

Technical field

This utility model relates in general to semiconductor fabrication, and particularly relates to chemical vapour deposition (CVD) (CVD) technique and relevant device, for keeping semiconductor wafer during technique。

Background technology

In the manufacture of light emitting diode (LED) and such as other high performance device of laser diode, photo-detector and field-effect transistor, chemical vapour deposition (CVD) (CVD) technique is typically used to use the material of such as gallium nitride to grow thin film stack on sapphire or silicon substrate。CVD instrument includes processing chamber, and this process chamber is that sealed environment is to allow the gas injected in the upper reaction of substrate (being generally the form of wafer) with growing film layer。The example of the current product line of this manufacture equipment is to be manufactured by the VeecoInstrumentsInc. of Plainview, NewYorkWith the EPIK of metal organic chemical vapor deposition (MOCVD) system series。

Control some technological parameters of such as temperature, pressure and gas flow rate to obtain desired crystal growth。Use different materials and technological parameter to grow different layers。Such as, typically, the compound semiconductor of such as Group III-V semiconductor the device formed is formed by using MOCVD to grow this compound semiconductor layer of continuous print。In the art, wafer is exposed in the combination of gas, and typically, this gas includes the metallo-organic compound in the source as III metal, and also includes the source of the V group element flowed on a surface of a wafer when wafer keeps at elevated temperatures。Generally, metallo-organic compound and group V source and be substantially not involved in the carrier gas combination of reaction, this carrier gas is such as nitrogen。One example of Group III-V semiconductor is gallium nitride, it is possible to form gallium nitride by the reaction of Organogallium compound and ammonia on the substrate with suitable interstitial void of such as sapphire wafer。During cvd nitride gallium and related compound at the general temperature that this wafer is maintained at about 1000-1100 DEG C。

Occurring in the MOCVD technique of crystal growth by the chemical reaction on substrate surface, it is necessary to take special care to control technological parameter to guarantee to carry out this chemical reaction required when。Negatively affect device quality even if change little in process conditions is likely to and produces yield。Such as, if cvd nitride gallium indium layer (galliumandindiumlayer), the change of wafer surface temperature will cause the composition of the layer deposited and the change of band gap。Because indium has relatively high vapour pressure, the layer deposited in the wafer area that surface temperature is higher will have relatively low indium ratio and bigger band gap。If the layer deposited is active layer, the luminescent layer of LED structure, then the radiation wavelength of the LED formed by this wafer also will fade to unacceptable degree。

Process in chamber at MOCVD, the semiconductor wafer of growing film layer is arranged on the atwirl carousel (carousel) being referred to as chip carrier thereon, is uniformly exposed in atmosphere in order to deposited semiconductor material with the surface making them within reaction chamber。Rotating speed is about 1000RPM。This chip carrier typically by the highly heat-conductive material machining of such as graphite out, and is often coated with the protective layer of such as carbofrax material。Each chip carrier has one group of circular depressions (indentation) or depression (pocket), is placed with single wafer in its top surface。Typically, wafer is supported for the lower surface positioned in spaced relation with each depression to allow the perimeter flowing gas at this wafer。At some examples of relevant technology described in U.S. patent application publication No.2012/0040097, U.S. patent No.8092599, U.S. patent No.8021487, U.S. patent application publication No.2007/0186853, U.S. patent No.6902623, U.S. patent No.6506252 and U.S. patent No.6492625, by reference the disclosure of which is herein incorporated。

Make the top surface with the chip carrier of the exposed surface of wafer upwardly toward gas distributing device at upper this chip carrier that supports of axle (spindle) in reaction chamber。As the shaft rotates, this gas is directed downwardly on the top surface of this chip carrier and flows to the periphery of this chip carrier through this top surface。From reaction chamber, the gas used is discharged by the port being arranged on below this chip carrier。Being maintained at by this chip carrier by heating element heater at the temperature of desired rising, this heating element heater is typically located in the stratie under the basal surface of this chip carrier。These heating element heaters are maintained at the temperature on the temperature desired by this wafer surface, typically, however this gas distributing device is maintained at just at temperature under desired reaction temperature to prevent gas premature reaction。Thus, heat is from this heating element heater to the transmission of the basal surface of this chip carrier and flows to single wafer upwardly through chip carrier。

Air-flow on wafer depends on the radial position of each wafer and changes, and due to during rotation its speed faster, the wafer of outermost position stands high flow velocities。Temperature non-uniformity is would be likely to occur, i.e. cold spot and focus even on each single wafer。The variable factor affecting the formation of temperature non-uniformity is the shape of the depression in chip carrier。Generally, pocket shapes forms circle in the surface of this chip carrier。Owing to chip carrier rotates, thus this wafer is subject to substantial centripetal force at its outmost edge (namely from the edge that rotating shaft is farthest) place, causes that wafer bears against the inwall of each depression in this chip carrier。In this case, between these external margin and edges of depression of wafer, there is close contact。Conduction of heat to the increase of these outermost parts of wafer causes bigger temperature non-uniformity, makes above-mentioned problem worse further。Make an effort to minimize temperature non-uniformity by increasing the gap between edge and the inwall of depression of wafer, including will a part that chip design is edge be flat (i.e. " flat " wafer)。This flat part of wafer produces the contact point of the inwall of gap reduction and this depression, thus relaxes temperature non-uniformity。Other factors affecting the thermal uniformity running through this wafer kept by this chip carrier include Heat transmission and the emission characteristics of chip carrier, and in conjunction with the layout of wafer pocket。

In order to realize temperature homogeneity, another desired characteristic of chip carrier is to increase to the volume of production of CVD technique。In increasing process throughput, the role of this chip carrier is to maintain substantial amounts of single wafer。The chip carrier influence of arrangement thermal model with more multi-wafer is provided。Such as, due to the radiant heat loss from chip carrier edge, the part of submarginal chip carrier tends to be at than under other part lower temperatures。

Accordingly, it would be desirable to the Practical Solution for chip carrier of the temperature homogeneity solved wherein in high density layouts and mechanical stress。

Utility model content

Chip carrier includes new depression and arranges。This layout described herein is easy to Heat transmission and is also had the high packed density (highpackingdensity) of the depression for circular wafer growth。

A kind of chip carrier, this chip carrier is configured to together with chemical vapor deposition unit to use, and this chip carrier includes: body, and this body has the top surface and basal surface that are arranged opposite to each other；Multiple depressions, the plurality of depression is limited in the described top surface of described chip carrier；This chip carrier includes the multiple depressions being made up of altogether 14 depressions, and each depression justifies layout along in two circles, and wherein the two is justified concentrically with respect to one another and concentric with the circular contour formed by the periphery of this top surface。

First circle in two circles of four depressions in multiple depressions is arranged, and second circle that ten depressions in multiple depression are in two circles is arranged。

First circle is surrounded by second circle。

This top surface includes the diameter of 300mm。

The depression diameter each including 50mm in multiple depressions。

Each including in multiple depressions has the radial wall of 430 μm of degree of depth。

This chip carrier includes the locking feature being arranged on this basal surface。

This locking feature is arranged in the geometric center place of this basal surface。

This locking feature is selected in the group that free spline, chuck or lock control accessory (keyedfitting) form。

This top surface and this basal surface all include a diameter, and the diameter of wherein this top surface is more than the diameter of this basal surface。

This chip carrier is configured to together with metal oxide chemical vapor deposition device to use。

Accompanying drawing explanation

After the detailed description considering the various embodiment of following this utility model together with accompanying drawing, it is possible to be more fully understood from this utility model, wherein:

Fig. 1 is the schematic diagram processing chamber of the MOCVD according to an embodiment。

Fig. 2 is the axonometric chart of the chip carrier with 14 depression configurations according to an embodiment。

Fig. 3 is the top view of the chip carrier with 14 depression configurations according to an embodiment。

Fig. 4 is the side view of the chip carrier with 14 depression configurations according to an embodiment。

Fig. 5 is the upward view of the chip carrier with 14 depression configurations according to an embodiment。

Fig. 6 is the part detail view of the chip carrier with 14 depression configurations according to an embodiment, it is shown that from the single depression of axonometric chart。

Detailed description of the invention

Fig. 1 illustrates the chemical vapor depsotition equipment according to an embodiment of the present utility model。Reaction chamber 10 defines process environments space。Gas distributing device 12 is arranged in the end of this cavity。There is the described end of gas distributing device 12 hold referred to here as " top " of reaction chamber 10。The top place in this chamber that this one end in this chamber is typically, but not necessarily, arranged under normal gravity reference frame。Thus, used herein in downward direction refer to the direction left from gas distributing device 12；And upwardly direction refers to the intracavity direction towards gas distributing device 12, regardless of whether these directions align with gravity direction up and down。Similarly, " top " and " end " surface of element is described herein with reference to the reference frame of reaction chamber 10 and gas distributing device 12。

Gas distributing device 12 is connected to the source 14,16 and 18 of the place's process gases for supplying the such as carrier gas and reacting gas that use in wafer processing process, and this reacting gas is such as metallo-organic compound and the source of V race metal。Gas distributing device 12 is arranged to the flowing receiving various gases and usual guiding place process gases in a downward direction。It is desirable that gas distributing device 12 is additionally coupled to cooling system 20, this cooling system is arranged to and makes liquid circulation through gas distributing device 12 to make the temperature of gas distributing device be maintained at desired temperature during operation。The cooling that can provide similar arranges that (not shown) is to cool down the wall of reaction chamber 10。Reaction chamber 10 is further equipped with gas extraction system 22, and this gas extraction system is arranged through the port (not shown) being located on or near bottom chamber and removes waste gas from the inside in chamber 10 so that allow there is continuous print air-flow in a downwardly direction from gas distributing device 12。

Axle 24 is arranged in intracavity so that the central axis 26 of axle 24 upwardly extends in side up and down。By including traditional rotation passing device (rotarypass-throughdevice) 28 of bearing and sealing member (not shown), axle 24 is mounted to chamber, axle 24 can be rotated about central axis 26, and keep the sealing between the wall of axle 24 and reaction chamber 10。This axle has the accessory 30 being positioned at its top end, being namely positioned at the end place closest to gas distributing device 12 of this axle。As discussed further below, accessory 30 is adaptable to be releasably engaged an example of the chip carrier maintaining body of chip carrier。In described specific embodiment, accessory 30 is generally toward the top convergent of axle and terminates at the Frusto-conical element of flat top surface。Frusto-conical element is the element of the frustum shape with circular cone。Axle 24 is connected to the rotary drive mechanism 32 of such as electric motor drive, and it is arranged as and makes axle 24 rotate about central axis 26。

Heating element heater 34 is arranged on intracavity and around axle 24 below accessory 30。Reaction chamber 10 is additionally provided with the entrance 36 leading to cup 38, and for closing and open the door 40 of this entrance。Exemplarily only depict door 40 in FIG, and it is removable to be shown as between closed position and open position, wherein this closed position is shown in solid, and in described closed position, the inside of this goalkeeper's reaction chamber 10 and cup 38 are isolated, and this open position is shown in broken lines at 40' place。This 40 is provided with in the suitable control and the actuating mechanism that move door between open and closed positions。In practice, this door can include moveable shutter (shutter) on direction up and down, for instance disclosed in U.S. patent No.7276124, by reference, the disclosure of which is incorporated herein by。This equipment described in FIG can also include loader mechanism (not shown), chip carrier can be moved to this intracavity from cup 38 and make this chip carrier engage with axle 24 in the operating condition by this loader mechanism, and also can make chip carrier removal axle 24 and enter cup 38。

This equipment also includes multiple chip carrier。Under the operating condition that figure 1 illustrates, in operating position, the first chip carrier 42 is arranged on the inside of reaction chamber 10, and the second chip carrier 44 is arranged in cup 38。Each chip carrier includes body 46, and this body 46 has the disc format (seeing Fig. 2) of central axis substantially。Body 46 is formed as symmetric about the axis。In operating position, the axis of chip carrier body overlaps with the central axis 26 of axle 24。Body 46 can be formed as the combination of single-piece or more than one piece。Disclosed in such as in U.S. patent application publication No.20090155028, by reference, the disclosure of which is incorporated herein by, the major part of hub portion (hub) that chip carrier body can include defining the zonule of the body around this central axis and the remainder that defines disc-shaped body。Body 46 is preferably formed by following material: this material does not pollute this technique and can withstand the temperature run in technique。Such as, the major part of this disk can be formed as, and it mostly or entirely by the material of such as graphite, carborundum or other refractory material is formed。Body 46 is generally of smooth top surface 48 and basal surface 52, and they extend generally parallel to each other and are approximately perpendicular to the central axis of this disk。Body 46 also has the one or more wafers maintenance features being adapted to keep multiple wafer。

In operation, for instance the wafer 54 of the Disc-like wafers formed by sapphire, carborundum or other crystalline substrates is arranged in each depression 56 of each chip carrier。Typically, the thickness that wafer 54 has is less than the size of its first type surface。Such as, the Circular wafer of diameter about 2 inches (50mm) can be about 430 μ m-thick or less。As shown in fig. 1, wafer 54 is disposed an outwardly facing the top surface of top so that this top surface exposes at the top place of chip carrier。It should be noted that in various embodiments, chip carrier 42 carries the wafer of varying number。Such as, in an example embodiment, chip carrier 42 may adapt to keep six wafers。In another example embodiment, as shown in Figure 2, this chip carrier keeps 25 wafers。

In typical MOCVD technique, will be loaded with the chip carrier 42 of wafer and be loaded into reaction chamber 10 from cup 38 and place in the operating position that figure 1 illustrates。In this case, the top surface of wafer is towards top, towards gas distributing device 12。Heating element heater 34 activated, and rotary drive mechanism 32 operates so that axle 24 rotates and therefore makes chip carrier 42 rotate around axis 26。Typically, the rotary speed rotating shaft 24 to turn every about minute 50-1500。Process gas supply unit 14,16 and 18 to activated to supply gas by gas distributing device 12。This gas transmits downwards towards chip carrier 42, through the top surface 48 of chip carrier 42 and wafer 54, and is sent to outlet down around the surrounding of chip carrier and is sent to gas extraction system 22。Thus, the top surface of chip carrier and the top surface of wafer 54 are exposed to place's process gases, and this place's process gases includes the mixing of the various gases supplied by various process gas supply units。Most typically ground, the carrier gas that the place's process gases at top surface place is mainly supplied by carrier gas feeding unit 16 forms。In typical chemical vapor deposition method, this carrier gas can be nitrogen, and be therefore mainly made up of the nitrogen with a certain amount of reacting gas composition in place's process gases at chip carrier top surface place。

Heat is transmitted the basal surface 52 to chip carrier 42 mainly through radiant heat transfer by heating element heater 34。Apply to be upward through the body 46 of chip carrier to the heat of basal surface 52 of chip carrier 42 and flow to the top surface 48 of chip carrier。The heat that traverse body is communicated up also extends through gap and is passed up to the basal surface of each wafer, and is passed up to the top surface of wafer 54 through this wafer。From the top surface 48 of chip carrier 42 and from the top surface of wafer to the cooler element processing chamber, for instance to processing the wall in chamber and to gas distributing device 12, radiations heat energy。Also from the top surface of the top surface 48 of chip carrier 42 and wafer to the process gas transmission heat through these surfaces。

In the embodiments described, this system includes multiple features, and these features are designed to determine the thermal uniformity on the surface of each wafer 54。In the present embodiment, temperature analysis system 58 receives temperature information, and this temperature information can include the temperature from temperature monitor 60 and monitoring temperature positional information。It addition, temperature analysis system 58 receives chip carrier positional information, it may be from rotary drive mechanism 32 in one embodiment。This information, temperature analysis system 58 has been had to construct the temperature profile of the depression 56 on chip carrier 42。Temperature profile represents the heat distribution on each depression 56 or the surface of wafer 54 that is included in。

Fig. 2 is the axonometric chart of the chip carrier 142 according to an embodiment。Fig. 3 is the top view of same chip carrier 142。Chip carrier 142 includes the body 146 with top surface 148 and is defined in 14 depressions 162 therein。In the embodiment illustrated in figs 2 and 3, depression 162 is arranged in two round R1 and R2, and each circle is all concentric with the circle limited by the outward flange of body 146。In radially inner R1, four depressions 162 are evenly spaced apart in orientation。Similarly, in radial direction cylindrical R2, ten depressions 162 are evenly spaced apart in orientation。Each depression 162 is formed in the aperture in body 146, and this aperture is substantially perpendicular to and extends with lower plane: wherein end face 148 is along this horizontal layout。

Being advantageous in that of the layout of the depression described in figs 2 and 3: while keeping the depression 162 of relative high density on top surface 148, which provide the thermal uniformity of aspiration level。In an embodiment, top surface 148 can have the diameter of about 300mm。Back pocket 162 be dimensioned so as to fit in this region。Such as, in an embodiment, depression 162 can have the diameter of about 50mm。

Fig. 3 further depict representational circle, and depression 162 is arranged in around this circle。In the embodiment illustrated in figure 3, having two circles, R1 and R2, each circle has different radiuses, and is arranged to concentrically with respect to one another and concentric with the circular contour of top surface 148。

Fig. 4 is the side view of the chip carrier 142 of Fig. 2 and 3, is shown in side view。In the view that figure 4 illustrates, it can be seen that the relative different in size between top surface 148 and basal surface 152。Especially, the top of the paper that top surface also shows in such as Fig. 4 and bottom extend, or further to radially extending in the view shown in figs 2 and 3。The each depression 162 previously described in figs 2 and 3 extends from top surface 148 towards basal surface 152。Basal surface 152 provides solid substrate, can be grown in chip carrier 142 by wafer in this solid substrate。

Fig. 5 is the upward view previously with respect to the chip carrier 142 described by Fig. 2 to Fig. 4。As shown in Figure 5, chip carrier 142 includes the locking feature 164 in the minds of in bottom surface 152。Locking feature 164 is configured to engage with other parts of the accessory 30 of the axle 24 such as previously described in FIG。In various embodiments, locking feature 164 can include such as spline (spline), chuck (chuck) or lock control accessory (keyedfitting)。Those skilled in the art is it will be appreciated that various mechanism can both apply angular momentum from adjacent elements to chip carrier 142。

Bottom surface 152 can be any material, and is designed in an embodiment be easy to Heat transmission。As it was previously stated, wish in an embodiment to transmit heat from neighbouring thermal element (such as the heating element heater 34 shown in Fig. 1) to bottom surface 152。Thus, bottom surface 152 can be relatively low refraction materials or can be coated by this material。

Chip carrier 142 can be formed by being suitable on it epitaxially grown any material, in an embodiment, for instance graphite or coated with graphite material。In other embodiments, it is possible to the material constituting chip carrier 142 is chosen as the desired lattice of coupling and arranges or size。Similarly, the wafer according to hope growth can use various sizes of depression 162。

Fig. 6 shows the partial perspective view of a depression 162。Each depression 162 includes sidewall 166, and it is substantially cylindrical。The bottom of the cylinder formed by sidewall 166 is substrate 168。In an embodiment, sidewall 166 can have the degree of depth of about 430 μm。

These embodiments are used as the purpose of example and unrestricted。Additional embodiment is in the claims。Although it addition, describe aspect of the present utility model with reference to specific embodiment, but those skilled in the art will recognize that and can make change when without departing from scope of the present utility model defined by the claims in form and details。

Claims (11)

1. a chip carrier, this chip carrier is configured to together with chemical vapor deposition unit to use, it is characterised in that this chip carrier includes:

Body, this body has the top surface and basal surface that are arranged opposite to each other；

Multiple depressions, the plurality of depression is limited in the described top surface of described chip carrier；

This chip carrier includes the multiple depressions being made up of altogether 14 depressions, and each depression is arranged along in two circles one circle, and wherein said two circles are concentrically with respect to one another and concentric with the circular contour formed by the periphery of described top surface。

2. chip carrier as claimed in claim 1, it is characterised in that

First circle in said two circle of four depressions in the plurality of depression is arranged；And

Second circle in said two circle of ten depressions in the plurality of depression is arranged。

3. chip carrier as claimed in claim 2, it is characterised in that described first circle by described second circle around。

4. described chip carrier as claimed in claim 1, it is characterised in that described top surface includes the diameter of 300mm。

5. the chip carrier as described in claim 1 or 4, it is characterised in that each depression in the plurality of depression all includes the depression diameter of 50mm。

6. the chip carrier as described in claim 1 or 4, it is characterised in that each depression in the plurality of depression all includes the radial wall with 430 μm of degree of depth。

7. chip carrier as claimed in claim 1, it is characterised in that described chip carrier also includes the locking feature being arranged on described basal surface。

8. chip carrier as claimed in claim 7, it is characterised in that described locking feature is arranged in the geometric center place of described basal surface。

9. chip carrier as claimed in claim 7 or 8, it is characterised in that described locking feature is selected in the group of free spline, chuck or lock control accessory composition。

10. chip carrier as claimed in claim 1, it is characterised in that described top surface and described basal surface all include a diameter, and the diameter of described top surface is more than the diameter of described basal surface。

11. chip carrier as claimed in claim 1, it is characterised in that described chip carrier is configured to together with metal oxide chemical vapor deposition device to use。