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# MULTILAYER DIAMOND HEAT SPREADERS FOR ELECTRONIC POWER DEVICES
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K. JAGANNADHAM
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Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695-7916, U.S.A.
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(Received 3 March 1998; accepted 4 June 1998)
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AbstractÐSingle layer diamond and multilayer diamond heat spreader substrates are prepared and bonded to device wafers of silicon and gallium arsenide. Metallization schemes for the diamond surface and the backside of the device wafers are described. Bonding of the device wafers to the diamond substrates using the high thermal conductivity gold±tin eutectic solder is carried out. Characterization of the bond for the distribution of dierent elements in the metallization layers and the solder, for the presence of microscopic defects such as voids and cracks, for the adhesion strength and for the stability of the bond under thermal cycling is performed. The heat spreader characteristics of the substrates with single and multlayer diamond are determined using infrared imaging of the bonded device wafers and compared with that of wafers bonded to metal substrates. Modeling and analysis of the eective thermal conductivity showed that the multilayer diamond substrates are better heat spreaders and reduce the device temperature so that the life of the electronic devices is prolonged. # 1998 Published by Elsevier Science Ltd. All rights reserved
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# 1. INTRODUCTION
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Heat spreading applications in electronics packaging, hitherto, are handled by high thermal conductivity materials such as beryllium oxide. Recent progress towards microminiaturization and high packaging densities leading to higher density of devices and modules as well as introduction of high frequency and high power devices compounded the problem of heat dissipation. It is realized that more ecient and fast dissipation of heat generated by the devices can only be met by the use of diamond ®lms.
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Power semiconductor devices rely upon the e- cient removal of heat for high frequency switching[1±3]. Natural diamond with high thermal conductivity (20 W/cm K), high electrical resistivity $( 1 0 ^ { 1 6 } \Omega \mathrm { c m } ) ^ { \dag }$ , low dielectric constant (5.7), high dielectric strength (106 V/cm), and matching thermal expansion coecient has been used in bonding devices such as laser diodes[4,5] to dissipate the thermal load. The advent of low pressure synthesis of diamond has helped to replace the high cost natural diamond. It is increasingly realized that the high thermal conductivity of synthetic diamond (10 W/cm K) by itself is not enough to dissipate the heat as the heat capacity of diamond is not large. Therefore, the electronic packaging industry can use the diamond heat spreaders provided the heat is absorbed by a high heat capacity substrate such as molybdenum or silicon nitride which can in turn be cooled by solid, liquid or vapor coolants. The important requirements that should be met before diamond coated heat spreaders can be used
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successfully include good adhesion of diamond to the substrates, stability of the bonded structure to thermal cycling, good heat spreader characteristics of the multilayer bonded structure, reliable process and bonding technology.
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We have developed the multilayer synthetic diamond coating technology on two types of substrates: molybdenum metallic substrate or silicon nitride ceramic substrate. The metallization and bonding procedure that provides reliable bonding to the device wafers such as silicon and gallium arsenide are also established. Characterization of the bonded microstructure, thermal stability and heat spreader properties are presented in the following.
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# 2. EXPERIMENTAL PROCEDURE
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Single layer continuous diamond ®lm of thickness 6 mm or multilayer diamond ®lm of thickness 10 mm was deposited on molybdenum or silicon nitride substrates of thickness 3±4 mm. The diamond layer in these ®lms was deposited by hot ®lament chemical vapor deposition. The details of diamond deposition were described in detail in our earlier work[6,7]. Single layer diamond ®lm deposited on molybdenum for 8 h to achieve a thickness of 10- 14 mm was found to delaminate from the diamond substrate. The large thermal stresses resulting from dierences in thermal expansion coecient between diamond $( \alpha = 3 . 1 \times 1 0 ^ { - 6 } / \mathrm { K } )$ and molybdenum carbide $( \alpha = 5 . 8 \times 1 0 ^ { - 6 } / \mathrm { K } )$ formed on molybdenum $( \alpha = 4 . 9 \times 1 0 ^ { - 6 } / \mathrm { K } )$ substrate were responsible for the delamination. The results of residual stress
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analysis using X-ray diraction and Raman spectroscopy are described more completely in a recent work[7]. The diamond ®lms grown on silicon nitride $( \alpha = 2 . 3 \times 1 0 ^ { - 6 } / \mathrm { K } )$ were not susceptible to delamination as a result of matching thermal expansion coecients[8,9]. The multilayer diamond coated substrates consist of a ®rst discontinuous layer of diamond deposited for 4 h under the same conditions as in the single layer diamond. In order to improve the adhesion of this ®rst layer of discontinuous diamond, an intermediate or second layer consisting of aluminium nitride of 1±2 mm thickness was deposited. The choice of aluminium nitride was based on the reasonably large value of its thermal conductivity (3.7 W/cm K), matching thermal expansion coecient $( 4 . 1 \times 1 0 ^ { - 6 } / \mathrm { K } )$ and high dielectric constant (8.8). In addition, the ease of deposition of high quality aluminium nitride ®lms was a contributing factor. Deposition of aluminium nitride was carried out either by pulsed laser ablation (KrF at 248 nm) or reactive magnetron sputtering[10] with the substrate maintained between 600 and 6508C. The experimental details of deposition of AlN are described in a recent publication[10]. Silicon carbide with a high thermal conductivity $( 5 \mathrm { { W / c m } \mathrm { { K } ) } }$ , matching thermal expansion coecient $( 4 . 3 \times 1 0 ^ { - 6 } / \mathrm { K } )$ and a high dielectric constant (9.0), although a good candidate for the embedding intermediate layer in the composite, cannot be deposited with the same good crystalline quality at these low temperatures. A ®nal layer of continuous diamond was deposited on the top for 6±8 h to provide a total thickness of 10±12 mm of diamond ®lm. Figure 1 shows a schematic illustration of the multilayer diamond ®lm bonded to a device wafer. The multilayer diamond ®lms on both molybdenum and silicon nitride substrates were found to be strongly adherent. Raman spectroscopy was used to characterize single layer and multilayer diamond ®lm and the results showed the characteristic diamond peak with the absence of either graphite or diamondlike phase[6,7]. X-ray diraction was used to determine
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Fig. 1. Schematic illustration of the structure of multilayer diamond heat spreader bonded to a device wafer.
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the crystalline quality of the aluminium nitride phase.
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Ecient heat dissipation from the devices was made possible by forming a solid state bond with the diamond substrate. The thermal resistance oered by the bond should be minimized at the same time the strength and thermal stability of the bond should be maintained. In order to enable the bond formation, metallization of diamond ®lm surface was carried out by deposition of titanium, gold and copper layers by laser physical vapor deposition. The multitarget deposition chamber was evacuated to a predeposition vacuum of better than $1 0 ^ { - 7 }$ Torr to prevent titanium oxide formation. Titanium was deposited at a substrate temperature of 6008C initially to prevent diamond decomposition to graphite followed by quickly heating to 7008C. Deposition of gold and copper ®lms was continued while cooling the substrate to room temperature. The thickness of each layer was estimated to be 0.3±0.5 mm. The deposition of copper layer, because of the high re¯ectivity, was carried out for 40 000 pulses to achieve a thickness of 0.5 mm. The choice of titanium to form the carbide with diamond, that of gold to prevent reaction of tin in gold±tin eutectic solder with titanium and that of copper to form a low temperature solid state bond with the solder was also found suitable for relaxation of thermal stresses during thermal cycling of the bond[9,11]. Similarly, the metallization of the backside of silicon wafer of thickness of 500 mm was carried out by deposition of titanium, gold and copper each for 20 000 pulses at room temperature. On the other hand, a dierent scheme for metallization of GaAs wafer was used which consisted of deposition of gold followed by that of Cu±Ge alloy by laser ablation with the wafer substrate maintained at room temperature. This metallization procedure in case of thin GaAs wafer was chosen so that the thermal stresses developed during cooling of the bond are relieved by plastic relaxation and secondly, wetting of the solder with the device wafers is accomplished[6]. The thickness of GaAs wafer was only 100 mm and yet the metallization and bonding procedure was carried out successfully without failure of the thin device wafer.
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The device wafer was bonded to the diamond substrate by heating with the low melting point (2808C) gold±tin eutectic alloy solder ®lm, placed in the middle, to a temperature of 3608C in a hydrogen atmosphere of 5 Torr followed by slow cooling to room temperature after 3 min. Spring loaded setup was used to apply small pressure so that a thin ®lm of the bond was formed. The high thermal conductivity and smaller thickness of the bond were important features that improve the eective thermal conductivity of the diamond heat spreader. Although gold±tin eutectic solder is not very ductile at lower temperatures, as will be seen in the follow-
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ing results, the ability to wet the copper layer helped the bond formation.
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In order to test the eective thermal conductivity and the heat spreader characteristics of the bonded single layer and multilayer diamond substrates, platinum resistance heater was deposited by laser physical vapor deposition on the front side of silicon wafer prior to bonding. Figure 2 is an infrared image of the platinum resistance heater after a constant power input. Calibration of the IR images enabled the temperature changes to be measured with time along the complete wafer for dierent ®xed values of power input into the heater[12].
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# 3. EXPERIMENTAL RESULTS
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The bonded specimens were characterized for adhesion strength, uniformity of composition of the bond, resistance to cracking or delamination under thermal cycling, and heat spreader characteristics or eective thermal conductivity. The strength of the bond was tested using a pull test[6] on a prototype silicon substrate on which diamond ®lm was deposited. The strength of the bond was found to be 5.0 MPa with the delamination taking place along titanium/diamond interface. Formation of titanium carbide is responsible for the adhesion strength of the metallization layers with diamond. Higher substrate temperature for deposition of titanium is expected to improve the formation of higher quality titanium carbide. The distribution of dierent elements present in the bonded wafers was determined by X-ray analysis and mapping of the crosssection samples prepared after thermal cycling. Figure 3 shows the X-ray maps of distribution of Si, Au, Sn, C, Al, Ti and Cu and scanning electron microscopy (SEM) image of a cross-section specimen of silicon wafer bonded to diamond/AlN/diamond/Si3N4 substrate prepared after thermal cycling between 25 and 1508C. The absence of silicon and carbon in the solder region helps to show
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Fig. 2. Infrared image of the resistance heater and the device wafer bonded to the diamond heat spreader.
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that diusion of these two elements is con®ned. Diusion of copper into the device wafer is prevented by the presence of gold and titanium layers. Also, the irregular interface between titanium, diamond (carbon) and the substrate seen in the SEM image is an artefact of cutting and irregular features seen on the surface. The signal from diamond was not very strong since carbon is a low atomic number element and in addition, the cross-section specimen was not polished to expose the diamond but more importantly to reveal the presence of voids or cracks in the bonded region that might have formed during thermal cycling. We have not observed the presence of any microscopic defects indicative of failure by cracking or delamination. Figure 4shows the distribution of dierent elements in a cross-section specimen of GaAs wafer bonded to multilayer diamond on molybdenum prepared by angle polishing at 118 to the plane of the bonded interface. As a result the interface region could be seen magni®ed with delineation of dierent regions. Similar to the results shown in Fig. 3, the distribution of dierent elements is con®ned with no interdiusion into the device GaAs wafer. A more important result common to both Figs 3 and 4 is that the metallization layers of titanium, gold and copper are distributed uniformly in the solder region which is expected since the diusion in the liquid phase $( 1 . 0 \times 1 0 ^ { - 4 } \mathrm { c m } ^ { 2 } / \mathrm { s } )$ is much faster and the solder layer is only a few micrometers in thickness.
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Thermal cycling was performed in two temperature ranges on dierent bonded specimens. In the ®rst, each cycle consisted of slow heating to 1508C from room temperature and cooling back in an atmosphere of nitrogen. Another set of specimens were subjected to the second range of thermal cycling wherein the specimens were rapidly heated to 1508C and quenched to ÿ208C in air. The specimens were examined by optical and scanning electron microscopy for delaminated regions either along diamond/substrate interface or diamond/ solder interface and for the presence of cracks in the wafer. The bonded specimens tested by slow cycling were very good without cracking or debonding. However, a small fraction of specimens of silicon wafer bonded to diamond/silicon nitride and subjected to rapid cooling to 208C showed delamination after several cycles. Figure 5 is the cross-section SEM image with X-ray maps of the silicon wafer bonded to diamond on silicon nitride which exhibited upon quenching resistance to delamination. Figure 6, on the other hand, shows the SEM image and X-ray maps of the planar region of the bond that failed by delamination. The interface in Fig. 5 was very good without the presence of any cracks and voids[9]. The distribution of all the elements in the X-ray maps shown in Fig. 6 was uniform and, in particular, there was no segregation that could be responsible for delamination. The high strain rate to which the specimens are sub-
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Fig. 3. X-ray mapping of dierent elements and SEM image of the cross-section of silicon wafer bonded to silicon nitride after thermal cycling between 25 and 1508C.
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Fig. 4. X-ray mapping of dierent elements and SEM image of the cross-section of GaAs wafer bonded to molybdenum after thermal cycling between 25 and 1508C.
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Fig. 5. X-ray mapping of dierent elements and SEM image of the cross-section of silicon wafer bonded to silicon nitride after rapid thermal cycling between ÿ20 and 1508C.
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jected during quenching may be responsible for failure along voids or cracks that could be present in the solder region. The brittle nature of the solder region may also be a contributing factor. Introduction of excess gold in the eutectic solder is expected to improve the ductility and the toughness of the solder and thereby prevent failure during quenching.
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The temperature raise on the wafer was measured along a line perpendicular to the platinum resistance heater for dierent values of power input. The rate of increase of temperature per unit power input was determined and shown in Fig. 7 for the three types of substrates, namely, bare molybdenum, molybdenum with single layer diamond, and molybdenum with diamond/AlN/diamond. These results clearly show that diamond heat spreaders perform much better than the bare molybdenum heat spreader and in addition, the multilayer diamond is better than the single layer diamond. Thus, AlN embedding layer has improved the eective thermal conductivity of multilayer diamond heat spreader[12].
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# 4. DISCUSSION
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The adhesion strength of the bond is found to be high in the device wafers bonded to diamond on molybdenum or silicon nitride substrates. X-ray maps of dierent elements showed the uniform distribution of dierent elements in the metallization and solder regions. Thus, the wetting reaction of
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solder with the device wafer and the diamond substrate was good without interdiusion of either carbon or silicon in case of silicon wafer and gallium or arsenic in case of GaAs wafer into the solder. Similarly, interdiusion of copper or gold into the device wafers was also absent. Diusion lengths of dierent elements in liquid solder within the bond processing period of 3-5 min is estimated to be 1- 2 mm which is considerably larger than the thickness of solder region. Therefore, the metallization layers and the solder region have become a single region with small gradients in concentration. Titanium carbide present across the interface with diamond provides the adhesion strength of the metallization layer to the substrate. The low conductivity of the metallization layers and that of the carbide layer is partly responsible for reduction of eective thermal conductivity associated with diamond heat spreader. However, the high heat capacity of these layers compensates for the low value of diamond. Thermal stresses in the thin GaAs device wafers should be reduced to prevent failure of the wafer by cracking. The plasticity of the metallization layer of copper±germanium on the backside is found to improve the toughness of the bond and prevent cracking of the thin (100 mm) GaAs wafer. Failure of the silicon wafers bonded to diamond substrate by delamination upon quenching below room temperature may be associated with phase transformation of tin in the tin-rich solder regions around 138C and the accompanying large volume change (27%). Although no detection of
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Fig. 7. Results of infrared imaging of silicon wafers bonded to bare molybdenum, single layer diamond coated molybdenum and multilayer diamond coated molybdenum substrates. Temperature at a ®xed point measured along the line perpendicular to the heater is plotted as a function of time. Average slope corresponds to that for three input power settings. For each substrate, the values of the slope differed only in the ®fth decimal place for the three power input settings[11].
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free tin or segregation of tin is observed in the SEM micrographs of the planar specimens shown in Fig. 6, we believe that there may be small amounts of tin responsible for the large volume change. Also, tin-rich solder may be more sensitive to high strain rates obtained by rapid cooling. We will use solders that are richer in gold to prevent delamination[13].
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The heat spreader characteristics of the multilayer diamond were found to be better than that of single layer diamond. Single layer polycrystalline diamond deposited on any substrate is known to contain microscopic voids and amorphous diamondlike carbon regions between the grain boundaries. These regions of discontinuity in heat transfer reduce the eective thermal conductivity. The eective thermal conductivity of diamond/AlN/diamond has been modeled using the multilayer arrangement shown in Fig. 8 with heat ¯ow in the direction normal to the interface[14]. Three types of interfaces between AlN and diamond are possible. These are a sharp interface, a graded interface and a diused interface. A sharp interface is de®ned by a discontinuous change in thermal conductivity from that of diamond to that of AlN. A graded interface is obtained when the thermal conductivity across the interface changes linearly from that of diamond to that of AlN across a region of width d of the interface. A diused interface, on the other hand, consists of a change in the thermal conductivity from that of diamond to that of AlN but not necessarily linearly and may also have a minimum or a maximum across the interface, as shown in Fig. 8. A graded or diused interface forms when the two adjacent phases interact to form a region of varying compo-
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sition. The presence of a maximum can only be fortuitous and has never been realized. The eective thermal conductivity, $K _ { \mathrm { e f f } } ,$ of this composite region may be obtained from[15]
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$$
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1 / K _ {\mathrm {e f f}} = V _ {\mathrm {d}} / K _ {\mathrm {d}} + V _ {\mathrm {a}} / K _ {\mathrm {a}} + 2 V _ {\mathrm {i}} / K _ {\mathrm {i}}, \tag {1}
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$$
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where the subscript d indicates diamond, a represents aluminium nitride, and i represents the interface formed on either side, as shown in Fig. 8. In the above equation the V represents the volume fraction and K the thermal conductivity of each phase and for the model shown in Fig. 8, the volume fraction is proportional to the dimension of each phase in the direction of heat ¯ow. The last term in the above equation can be determined using any variation in the thermal conductivity across the
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Fig. 8. Schematic illustration of a diused interface formed between diamond and aluminum nitride. A graded or smooth interface is formed when there is no minimum in the interface. A sharp interface is formed when the interface volume is zero.
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Fig. 9. Eective thermal conductivity of the composite structure illustrated in Fig. 8 shown as a function of the volume fraction of the interface. Interfacial thermal resistance for a sharp interface is considered to be zero. Volume fraction of the interface region plus the AlN phase is kept constant at 0.0588.
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interface. Thus for a graded interface, $1 / K _ { \mathrm { i } } { = } 1 /$ $( \alpha d ) \mathrm { l n } ( K _ { \mathrm { d } } / K _ { \mathrm { a } } )$ where $\alpha = ( K _ { \mathrm { d } } { - } K _ { \mathrm { a } } ) / d .$ On the other hand, the equivalent expression for a diused interface takes the form
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$$
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1 / K _ {\mathrm {i}} = (1 / d \alpha_ {1}) \ln \left(K _ {\mathrm {d}} / K _ {\mathrm {i}}\right) + (1 / d \alpha_ {2}) \ln \left(K _ {\mathrm {i}} / K _ {\mathrm {a}}\right) ], \tag {2}
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$$
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where $\alpha _ { 1 } = ( K _ { \mathrm { d } } { - } K _ { \mathrm { a } } ) / d _ { 1 } , \alpha _ { 1 } = ( K _ { \mathrm { i } } { - } K _ { \mathrm { a } } ) / d _ { 2 } .$ d1 and d2 are the dimensions of the interfacial regions $( d = d _ { 1 } + d _ { 2 } )$ , with changes in thermal conductivity, as shown in Fig. 8. For a sharp interface, $V _ { \mathrm { i } } { = } 0$ but an interfacial thermal barrier resistance can be de®ned in the form $2 V _ { \mathrm { i } } / K _ { \mathrm { i } } { = } 2 V _ { \mathrm { a } } / d h _ { \mathrm { c } }$ . The eective thermal conductivity in the presence of a sharp interface is controlled by the non-dimensionless parameter, $K _ { \mathrm { a } } / d h _ { \mathrm { c } }$ . When $K _ { \mathrm { a } } / d h _ { \mathrm { c } }$ becomes in®nitely large $( h _ { \mathrm { c } } { = } 0 )$ , the eective thermal conductivity corresponds to the value for polycrystalline diamond with a dispersed void space.
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A detailed numerical analysis of the eective thermal conductivity of the diamond/AlN/diamond composite is presented in Ref.[14] for three dierent situations, namely, when the interfacial layer is formed in the AlN region or in the diamond region or in both the AlN and diamond regions equally. The results of analysis when the diused interface is formed in the AlN region are presented in Fig. 9. The eective thermal conductivity of the composite is seen to increase with increase in volume fraction of the interfacial region although a minimum is present in the thermal conductivity across the interface. The diamond layer of thickness 4 mm on either side surrounds the AlN region of 0.5 mm with the thickness of interface region increase and that of AlN decrease for larger volume fraction of the interface. The thermal conductivity of diamond was assumed to be 20 W/cm K and that of AlN at 3.7 W/cm K with the minimum value of the thermal conductivity across the interface chosen to be 1.0 W/cm K. It is seen that the composite with the graded interface has the highest thermal conductivity with that of diused interface at the intermediate value and that
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with sharp interface lowest when the interfacial thermal resistance was zero. If the interfacial thermal resistance were to be very high as in the case of diamond ®lm with voids across the interface, the eective thermal conductivity of the composite with sharp interface will be very small. We have not assumed this situation since percolation paths are also available for heat ¯ow. These results shown in Fig. 9 illustrate that the eective thermal conductivity of diamond/AlN/diamond composites will be higher than that of polycrystalline synthetic diamond with diamondlike carbon or voids.
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# 5. CONCLUSIONS
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Diamond heat spreaders were successfully bonded to device wafers of either silicon or GaAs using gold±tin eutectic solder with proper metallization procedures. AlN embedding layer improves the adhesion strength of diamond to molybdenum or silicon nitride, thermal stability of the bond and the heat spreader characteristics. In the present study, we have shown that multilayer diamond ®lms exhibit higher eective thermal conductivity than either single layer diamond or molybdenum. Modeling and analysis of the interface region suggests that AlN ®lm replaces the diamondlike carbon phase and void space between large grains of diamond and thereby volume fraction of higher conductivity region is improved in multilayer diamond composites. Further, we have shown that the multilayer diamond heat spreaders are helpful to lower the temperature of the electronic devices and thereby prolong their life.
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AcknowledgementsÐThis research is supported by the Division of DMII, NSF. Also, this research is sponsored by SURA and the Assistant Secretary for Energy Eciency and Renewable Energy, Oce of Transportation Technologies, as part of the HTML User Program, ORNL, managed by Lockheed Martin Energy Research Corp. for the U.S. DOE under contract number DE-AC05-96OR22464.
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# REFERENCES
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1. Kuttel, O. M., Schaller, E., Osterwalder, J. and Schlapbach, L., Diamond Related Mater., 1995, 4, 612.
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2. Boudreaux, P. J., Applications of diamond ®lms and related materials: 3rd Int. Conf., ed. A. Feldman et al. NIST Special Publication 885, Washington, DC, 1995.
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3. Ashley, S., Mech. Eng., 1990, 112, 54.
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4. Behr, W. and Luy, J. F., IEEE Electron Device Lett., 1990, 11, 206.
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5. Ukita, H., Nakada, H. and Abe, T., Jpn. J. Appl. Phys., 1992, 31, 524.
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6. Fan, W. D., Jagannadham, K. and Narayan, J., Proc. MRS Symposium, Vol. 416. Boston, MA, 1995.
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7. Jagannadham, K., Watkins, T. R. and Narayan, J., Proc. MRS Symposium, Vol. 458. Boston, MA, 1996.
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8. Touloukin, Y. S., Kirby, R. K., Taylor, R. E. and Lee, T. Y. R. (Eds), Thermal expansion (nonmetallic solid). IFI Plenum, New York, 1977.
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9. Ramaswamy, B. and Jagannadham, K., Proc. MRS Symposium. Boston, MA, 1997.
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10. Jagannadham, K., Sharma, A. K., Wei, Q., Kalayanaraman, R. and Narayan, J., J. Vac. Sci. Tech. Submitted.
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11. Katz, A., Balocchi, F., Lane, E., Lee, C. H., Hall, C., Doting, J., Grijsbach, C. and Harris, K., J. Appl. Phys., 1994, 75, 563.
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12. Jagannadham, K., Dinwiddie, R. B. and Narayan, J., Proc. MRS Symp., Vol. 445. Boston, MA, 1996.
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13. Yost, F. G., Karnowsky, M. M., Drotning, W. D. and Gieske, J. H., Met. Trans. A, 1990, 21, 1885.
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14. Jagannadham, K., J. Appl. Phys. Submitted.
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15. Hasselman, D. P. and Johnson, L. F., J. Compos. Mater., 1987, 21, 508.
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After Width: | Height: | Size: 6.3 KiB |
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After Width: | Height: | Size: 17 KiB |
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After Width: | Height: | Size: 13 KiB |
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After Width: | Height: | Size: 75 KiB |
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After Width: | Height: | Size: 39 KiB |
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After Width: | Height: | Size: 7.9 KiB |
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After Width: | Height: | Size: 52 KiB |
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After Width: | Height: | Size: 15 KiB |
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After Width: | Height: | Size: 19 KiB |
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After Width: | Height: | Size: 14 KiB |
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After Width: | Height: | Size: 9.6 KiB |
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After Width: | Height: | Size: 4.8 KiB |
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After Width: | Height: | Size: 14 KiB |
Reference in New Issue
Block a user