CN219040465U - Power module - Google Patents

Abstract

The utility model provides a power module which comprises a substrate, a plurality of chips, a plurality of support columns, a heat dissipation plate and a plurality of joint bodies. The substrate comprises a wiring layer. The chips are located on the wiring layer of the substrate, and any one of the chips comprises a source electrode, a drain electrode and a grid electrode. The plurality of support columns are located on the chip. The heat dissipation plate is positioned on the support column and connected with the support column. The plurality of joint bodies are positioned on the heat dissipation plate and connected to the wiring layer. Some embodiments of the present utility model may utilize support posts, heat sinks, and bonding materials to improve the reliability of the power module and reduce stress buildup of the power module. In addition, the current equalizing effect and the heat dissipation effect of the power module can be improved.

Description

Power module

Technical Field

Some embodiments of the utility model relate to power modules.

Background

A power module is a package that contains a plurality of power components (e.g., power semiconductor chips). The power component may be disposed on the substrate and the electrodes on the power component are connected to specific terminals by traces. Applications of power modules are common in transportation and industrial systems, for example, power modules may be used in motor drives, frequency converters, power supplies, and the like.

Disclosure of Invention

Some embodiments of the utility model provide a power module, which includes a substrate, a plurality of chips, a plurality of support columns, a heat dissipation plate, and a plurality of joints. The substrate comprises a wiring layer. The chips are located on the wiring layer of the substrate, and any one of the chips comprises a source electrode, a drain electrode and a grid electrode. The plurality of support columns are located on the chip. The heat dissipation plate is positioned on the support column and connected with the support column. The plurality of joints are connected with the heat dissipation plate and the wiring layer.

In some embodiments, there is a gap between the chips, and the bond is located on the heat spreader plate and directly over the chips and the gap.

In some embodiments, the bond is a plurality of wires or a plurality of ribbons.

In some implementations, any of the support posts connects the source of any of the chips with the heat spreader plate.

In some embodiments, the power module further includes a plurality of wires on the chip and connected to the trace layer, and the trace layer further includes a drain pattern, a source pattern, and a gate pattern. The chips are placed on the drain patterns, and the drain of any one of the chips is connected to the drain pattern. The source electrode pattern is adjacent to and separated from the drain electrode pattern, wherein the junction connects the source electrode pattern and the heat dissipation plate. The gate pattern is adjacent to and separated from the drain pattern, wherein the wire connects the gate of any one of the gate pattern and the chip.

In some embodiments, the power module further comprises a first terminal, a second terminal, and a fourth terminal. The first terminal is connected to the source pattern. The second terminal is connected to the drain pattern. The fourth terminal is connected to the gate pattern.

In some embodiments, the trace layer further includes a source pattern, a drain pattern, and a gate pattern. The chips are placed on the source patterns, and the source of any one of the chips is connected to the source pattern. The drain pattern is adjacent to the source pattern and separated from the source pattern, wherein the junction connects the drain pattern and the heat dissipation plate. The gate pattern is adjacent to and separated from the source pattern, wherein the gate pattern connects the gate of any one of the chips.

In some embodiments, the heat spreader plate includes a recessed structure on the support post.

In some embodiments, the bond is a plurality of metal posts or a plurality of bonding materials.

In some embodiments, the heat spreader plate is concavely folded toward the trace layer, and a portion of the concavely folded heat spreader plate extends along the trace layer.

Some embodiments of the present utility model may utilize support posts, heat sinks, and bonding materials to improve the reliability of the power module and reduce stress buildup of the power module. In addition, the current equalizing effect and the heat dissipation effect of the power module can be improved.

Drawings

Fig. 1 illustrates a cross-sectional view of a power module in accordance with some embodiments of the utility model.

Fig. 2 illustrates a top view of a power module according to some embodiments of the utility model.

Fig. 3 shows an enlarged view of the region M of fig. 2.

Fig. 4 is a top view of a power module according to other embodiments of the present utility model.

Fig. 5 shows a top view of a power module according to further embodiments of the utility model.

Fig. 6 shows a top view of a power module according to further embodiments of the utility model.

Fig. 7 is a top view of a power module according to other embodiments of the present utility model.

Fig. 8 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 9 is a top view of a power module according to other embodiments of the present utility model.

Fig. 10 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 11 is a top view of a power module according to other embodiments of the utility model.

Fig. 12 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 13 is a top view of a power module according to other embodiments of the utility model.

Fig. 14 is a top view of a power module according to other embodiments of the utility model.

Fig. 15 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 16 is a top view of a power module according to other embodiments of the utility model.

Fig. 17 is a top view of a power module according to other embodiments of the present utility model.

Fig. 18 is a top view of a power module according to other embodiments of the present utility model.

Fig. 19 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 20 is a top view of a power module according to other embodiments of the utility model.

Fig. 21 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 22 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 23 is a top view of a power module according to other embodiments of the utility model.

Fig. 24 is a cross-sectional view of a power module according to further embodiments of the present utility model.

Fig. 25 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Fig. 26 shows a cross-sectional view of a power module according to further embodiments of the utility model.

Detailed Description

Fig. 1 illustrates a cross-sectional view of a power module 100 in accordance with some embodiments of the utility model. Fig. 2 illustrates a top view of a power module 100 according to some embodiments of the utility model, and fig. 1 is a view along section A-A of fig. 2. Referring to fig. 1 and 2, the power module 100 includes a substrate 110, a plurality of chips 120, support columns 130, a heat dissipation plate 140, a bonding body 152 and wires 154. The substrate 110 includes a trace layer 112. The chip 120 is disposed on the trace layer 112 of the substrate 110, and any one of the chips 120 includes a source 122, a drain 124 and a gate 126. The support columns 130 are located on the chip 120. The heat dissipation plate 140 is positioned on the support column 130 and connected to the support column 130. The bonding body 152 connects the heat spreader 140 and the trace layer 112. Wire bond 154 is located on chip 120 and connects to trace layer 112.

The substrate 110 may include a trace layer 112, an insulating layer 114, and a conductive layer 116. The trace layer 112 is on the insulating layer 114, and the insulating layer 114 is on the conductor layer 116. That is, the conductor layer 116 is completely separated from the trace layer 112 by the insulating layer 114. The trace layer 112 may include a drain pattern 112D, a source pattern 112S and a gate pattern 112G. The conductive layer 116 may be used for heat dissipation, and the conductive layer 116 may also facilitate connection of the substrate 110 to an underlying substrate (hereinafter referred to as the substrate 160). In some embodiments, the trace layer 112 and the conductor layer 116 may be made of metal, such as copper, and the insulating layer 114 may be made of ceramic. The source pattern 112S is adjacent to the drain pattern 112D and separated from the drain pattern 112D, and the gate pattern 112G is adjacent to the drain pattern 112D and separated from the drain pattern 112D. In some embodiments, the shapes of the source pattern 112S, the drain pattern 112D and the gate pattern 112G are as shown in fig. 2, for example, the drain pattern 112D is on two sides of the gate pattern 112G of the power module 100, and the source pattern 112S is on two sides of the complete portion of the drain pattern 112D. However, fig. 2 is only schematic, and is not intended to limit the shapes or design configurations of the source pattern 112S, the drain pattern 112D, and the gate pattern 112G.

The chips 120 are arranged on the substrate 110. Each chip 120 includes a semiconductor layer 121, a source 122, a drain 124, and a gate 126. The source electrode 122 and the gate electrode 126 are on one side of the semiconductor layer 121, the drain electrode 124 is on the other side of the semiconductor layer 121, and the surface of the source electrode 122 and the gate electrode 126 is opposite to the surface of the drain electrode 124. Specifically, the chips 120 are disposed on the drain patterns 112D, and the drain 124 of any one of the chips 120 is connected to the drain patterns 112D through the bonding material 172. The chip 120 may be any suitable chip, such as a metal oxide semiconductor field effect transistor (Metal Oxide Semiconductor Field Effect Transistor, MOSFET) chip, an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT) chip, a diode (diode) chip.

The support column 130 is located on the source 122 of the chip 120, and the heat dissipation plate 140 is located on the support column 130 and covers the support column 130. That is, any one of the support columns 130 connects the source 122 of any one of the chips 120 with the heat dissipation plate 140. Specifically, any one of the support columns 130 is connected to the source 122 of any one of the chips 120 through a bonding material 174, and is connected to the heat dissipation plate 140 through a bonding material 176. Since the heat dissipation plate 140 covers the plurality of chips 120 at the same time with the gap G between the chips 120, the heat dissipation plate 140 also covers the gap G between the chips 120 at the same time. The support post 130 and the heat dissipation plate 140 are made of conductive materials. In some embodiments, the support posts 130 may be made of copper or copper molybdenum laminates. The heat dissipation plate 140 may be made of copper.

The bonding body 152 is disposed on the heat spreader 140 and electrically connected to the trace layer 112. Specifically, the bonding body 152 electrically connects the source pattern 112S and the heat dissipation plate 140. The bonding body 152 may be located directly above the chip 120, and the bonding body 152 may also be located on the heat dissipation plate 140 and directly above the chip 120 and the gap G. When the bonding body 152 electrically connects the source pattern 112S and the heat dissipation plate 140, the bonding body 152 is not completely straightened, in other words, the bonding body 152 has a certain curvature (or the bonding body 152 is relaxed). When the bonded body 152 expands thermally and contracts cold due to the heat emitted from the chip 120, stresses are less likely to accumulate in the bonded body 152. In some embodiments, the bonding body 152 may be bonded to the substrate 110 and the heat dissipation plate 140 using ultrasonic bonding at normal temperature.

The wire 154 is disposed on the chip 120 and electrically connected to the trace layer 112. Specifically, the wire 154 electrically connects the gate pattern 112G and the gate 126 of any one of the chips 120. The wire bond 154 may be made of any suitable conductor, such as aluminum, aluminum clad copper, copper. In some embodiments, the wire bonds 154 may be bonded to the substrate 110 and the die 120 using ultrasonic bonding at ambient temperature.

The power module 100 also includes a backplane 160. The bottom plate 160 is located under the substrate 110. In some embodiments, the bottom plate 160 includes a columnar structure at the bottom for increasing the heat dissipation area of the power module 100.

The power module 100 also includes bonding materials 172, 174, 176, and 178. The bonding material 172 electrically connects the chip 120 and the drain pattern 112D of the trace layer 112. The bonding material 174 electrically connects the support pillars 130 and the chip 120. The bonding material 176 electrically connects the support post 130 and the heat dissipation plate 140. The bonding material 178 electrically connects the substrate 110 and the base plate 160. The bonding materials 172, 174, 176, and 178 may be made of a relatively low hardness conductive material, such as solder, silver frit, etc., or other conductive material, such as copper frit. The bonding materials 172,174, 176 and 178 may be selected to have a lower hardness than the object to which they are attached. For example, the bonding material 174 has a lower hardness than the support columns 130 and the chips 120.

The power module 100 further includes a first terminal 182, a second terminal 184, and a molding compound 190. The first terminal 182 is electrically connected to the source pattern 112S. The second terminal 184 is electrically connected to the drain pattern 112D. When the power module 100 is a molding (molding) type module, the power module 100 further includes a third terminal 186, the third terminal 186 is located on the gate pattern 112G, and the third terminal 186 is a needle terminal. The third terminal 186 can provide a voltage to the gate 126 of the chip 120 to turn on the chip in the power module 100, so that the source 122 and the drain 124 of the chip have a potential difference, and a current can flow along the second terminal 184 through the drain pattern 112D, the drain 124 of the chip 120, the source 122 of the chip 120, the support post 130, the heat sink 140, the bonding body 152, and the source pattern 112S to the first terminal 182. In other words, the chips 120 of the power module 100 are connected in parallel. The encapsulation compound 190 covers the base plate 160, the substrate 110, the heat spreader 140, the first terminals 182, the second terminals 184, and the chip 120. In some embodiments, the encapsulation glue 190 is on the base plate 160 and encapsulates all of the objects of the power module 100. In some embodiments, the encapsulation glue 190 may be made of epoxy, silicone, or the like. It should be noted that the encapsulation compound 190 is omitted in fig. 2 for simplicity of the drawing.

Fig. 3 shows an enlarged view of the region M of fig. 2. Fig. 3 highlights the structure of the power module 100 of some embodiments of the utility model to advantage. Referring to fig. 1 and 3, the support columns 130 and the heat dissipation plate 140 are matched with the bonding materials 174 and 176 to reduce stress of the power module 100 and improve reliability of the power module 100. Specifically, the support post 130 is electrically connected to the heat spreader 140 and the source 122 of the chip 120, and the bonding material 174 bonds the chip 120 and the support post 130, and the bonding material 176 bonds the support post 130 and the heat spreader 140. Therefore, if the heat spreader 140 is subjected to external forces during the process of the power module 100, the support posts 130 and the bonding materials 174 and 176 can act as buffers to reduce the stress accumulated between the bonding material 174 and the chip 120. For example, the support columns 130 have a certain height, so that a certain distance is provided between the heat sink 140 and the chip 120, and the hardness of the bonding materials 174, 176 is smaller, so that the bonding materials 174, 176 can provide buffering when the heat sink 140 moves to keep the support columns 130 moving. In addition, since the heat dissipation plate 140 does not extend to the trace layer 112 and is bonded thereto, the expansion coefficient mismatch and thermal stress accumulation problem between materials due to the temperature rise and fall in the bonding process (such as solder or silver sintering process) are relatively small.

Thermal stresses caused by the required high temperature do not accumulate in the trace layer 112.

In addition, the support columns 130 and the heat dissipation plate 140 according to some embodiments of the present utility model can be used to increase the current uniformity and the heat dissipation capability. The heat dissipation plate 140 is electrically connected to the chips 120 at the same time, and covers the gaps G between the chips 120 at the same time. The joint bodies 152 may be densely distributed on the heat dissipation plate 140. Some of the bonds 152 may be directly above the chips 120 and other bonds 152 may be above the gaps G between the chips 120. In this way, when the current flows to the source 122 of the chip 120, each of the junctions 152 can uniformly distribute the current flowing to the source 122 of the chip 120, so as to achieve the purpose of uniform current. The heat emitted by the chip 120 during operation can be dissipated upward along the support columns 130 and through the heat dissipation plate 140 (e.g., path P1 of fig. 1), or be transferred to the joint body 152 through the heat dissipation plate 140, or be transferred downward to the bottom plate 160 (e.g., path P2 of fig. 1). Since the heat dissipation plate 140 has a larger area than the upper surface of the chip 120, heat emitted from the chip 120 can be dissipated greatly. Less heat is transferred to the joint 152 and thermal stresses are less likely to be generated in the joint 152. In some embodiments, the bond 152 may be a wire bond, as shown in fig. 3. When the bond 152 is wire bonded, the wire diameter W1 of the wire bond is between 75 microns and 500 microns. The bond 152 may be made of any suitable conductor, such as aluminum, aluminum clad copper, copper.

Fig. 4 illustrates a top view of a power module 100 according to further embodiments of the present utility model. The power module 100 of fig. 4 is similar to the power module 100 of fig. 2, except that the heat sink 140 in the power module 100 of fig. 2 extends directly above the gate 126 of the chip 120, whereas the heat sink 140 in the power module 100 of fig. 4 does not extend directly above the gate 126 of the chip 120. The area of the heat dissipation plate 140 of the power module 100 of fig. 4 is still larger than the area of the upper surface of the chip 120, so that a sufficient heat dissipation effect can be provided.

Fig. 5 illustrates a top view of a power module 100 according to further embodiments of the present utility model. The difference from fig. 2 is that the power module 100 of fig. 5 does not include the third terminal 186. The power module 100 of fig. 5 includes a fourth terminal 188, and the fourth terminal 188 is electrically connected to the gate pattern 112G. The power module 100 may further include a gate pattern 112G1, and the fourth terminal 188 is located on the gate pattern 112G1. The fourth terminal 188 is electrically connected to the gate pattern 112G through a bridge 189. The bridge 189 is a conductor and contacts only the gate patterns 112G and 112G1. Therefore, the fourth terminal 188 is not electrically connected to the source pattern 112S and the drain pattern 112D. A voltage may be provided from the fourth terminal 188 to the gate 126 of the chip 120 to turn on the chip in the power module 100, such that the source 122 and the drain 124 of the chip have a potential difference. Current may flow along the second terminal 184 through the drain pattern 112D, the drain 124 of the chip 120, the source 122 of the chip 120, the support post 130, the heat spreader 140, the bonding body 152, the source pattern 112S to the first terminal 182.

Fig. 6 shows a top view of a power module 100 according to further embodiments of the utility model. The power module 100 of fig. 6 is similar to the power module 100 of fig. 2, except that the joint 152 of the power module 100 of fig. 6 is a plurality of ribbons, and the width W2 of the ribbons is between 1 mm and 2 mm. When the junction 152 is a ribbon, the width of the ribbon is wider, so that the purpose of uniform current magnitude can be achieved. In addition, the bonding body 152 is directly located on the heat dissipation plate 140, not contacting the chip 120, and thus the width of the bonding body 152 may not be limited by the size of the chip 120.

Fig. 7 illustrates a top view of a power module 100 according to further embodiments of the present utility model. The power module 100 of fig. 7 is similar to the power module 100 of fig. 5, except that the joint 152 of the power module 100 of fig. 7 is a plurality of ribbons, and the width W2 of the ribbons is between 1 mm and 2 mm.

Fig. 8 illustrates a cross-sectional view of a power module 100 according to further embodiments of the present utility model. Fig. 9 is a top view of a power module 100 according to other embodiments of the present utility model, and fig. 8 is a view along a section a '-a' of fig. 9. Referring to fig. 8 and 9, the power module 100 of fig. 8 is similar to the power module 100 of fig. 1, except that the drain electrode 124 of the chip 120 of fig. 8 is disposed upward, and the positions of the drain pattern 112D and the source pattern 112S are opposite to the power module 100 of fig. 1. Specifically, the drain 124 of the chip 120 of fig. 8 is facing upward, and the source 122 and gate 126 of the chip 120 are facing downward. The trace layer 112 of the power module 100 of fig. 8 includes a source pattern 112S, a drain pattern 112D and a gate pattern 112G. The chips 120 are disposed on the source patterns 112S, and the source 122 of any one of the chips 120 is connected to the source patterns 112S. The drain pattern 112D is adjacent to the source pattern 112S and separated from the source pattern 112S. The junction 152 connects the drain pattern 112D and the heat sink 140. The gate pattern 112G is adjacent to the source pattern 112S and separated from the source pattern 112S, wherein the gate pattern connects the gate 126 of any one of the chips 120. The drain electrode 124 of the chip 120 is electrically connected to the support pillar 130, the heat dissipation plate 140 and the drain electrode pattern 112D through the bonding material 172, the source electrode 122 of the chip 120 is electrically connected to the source electrode pattern 112S through the bonding material 174, and the gate electrode 126 of the chip 120 is electrically connected to the gate electrode pattern 112G through the bonding material 173. That is, the power module 100 of fig. 8 does not include the wire bonds 154. The bonding material 173 may be made of a relatively low hardness conductive material, such as solder, silver frit, or the like.

Fig. 10 illustrates a cross-sectional view of a power module 100 according to further embodiments of the present utility model. Fig. 11 is a top view of a power module 100 according to other embodiments of the present utility model, and fig. 10 is a cross-section a "-a" along fig. 11. Referring to fig. 10 and 11, the power module 100 of fig. 10 is similar to the power module 100 of fig. 1, except that the heat dissipation plate 140 of fig. 10 has a plurality of holes 140H. The hole 140H does not overlap the junction 152. The hole 140H may be used to reduce stress and deformation of the heat dissipation plate 140. The position of the hole 140H may be designed according to the size and thickness of the heat sink 140 and the bonding position of the heat sink 140 and the bonding body 152. The heat dissipation plate 140 having the holes 140H may be applied to all embodiments of the present utility model.

Fig. 12 shows a cross-sectional view of a power module 100 according to further embodiments of the utility model. Fig. 13 shows a top view of a power module 100 according to further embodiments of the present utility model, and fig. 12 is shown along section a '"-a'" of fig. 13. Referring to fig. 12 and 13, the power module 100 of fig. 12 is similar to the power module 100 of fig. 1 and 2, except that the arrangement of the chips 120 is different from the shape of the trace layer 112. In fig. 12, the trace layer 112 includes a drain pattern 112D, a source pattern 112S and a gate pattern 112G. The source pattern 112S is adjacent to the drain pattern 112D and separated from the drain pattern 112D. The gate pattern 112G is adjacent to the source pattern 112S and separated from the source pattern 112S. The drain pattern 112D, the source pattern 112S and the gate pattern 112G may be as shown in fig. 13.

Unlike the power module 100 of fig. 2, the gate pattern 112G of the power module 100 of fig. 13 is flanked by the source pattern 112S, but not the drain pattern 112D. The chip 120 is on the drain pattern 112D of the trace layer 112, and the drain 124 of the chip 120 is electrically connected to the drain pattern 112D of the trace layer 112. The chips 120 may be arranged in a matrix of two rows (e.g., 2x2, 3x2, 4x2, etc.), with the gates 126 of the chips 120 of each row being remote from each other. The chips 120 in the same matrix are connected to the same heat sink 140. The heat sink 140 exposes the gate 126 of the chip 120. The bonding bodies 152 are electrically connected to the source patterns 112S and the heat dissipation plate 140, and each bonding body 152 can be electrically connected to the source electrodes 122 of the chips 120 to the source patterns 112S at the same time. The gate pattern 112G is electrically connected to the gate 126 of the chip 120. Specifically, the gate electrode 126 and the gate pattern 112G of the chip 120 may be electrically connected through the wire 154. Each wire 154 may also be electrically connected to the gate 126 of the plurality of chips 120 to the gate pattern 112G at the same time. When the power module 100 is configured as shown in fig. 13, the bonding body 152 is more beneficial to improving current uniformity between different chips 120.

Fig. 14 shows a top view of a power module 100 according to further embodiments of the utility model. The power module 100 of fig. 14 is similar to the power module 100 of fig. 13, except that the junction 152 of the power module 100 of fig. 14 is a plurality of ribbons. When the junction 152 is a ribbon, the width of the ribbon is wider, so that the purpose of uniform current magnitude can be achieved. In addition, the bonding body 152 is directly located on the heat dissipation plate 140, not contacting the chip 120, and thus the width of the bonding body 152 may not be limited by the size of the chip 120.

Fig. 15 shows a cross-sectional view of a power module 100 according to further embodiments of the present utility model. Fig. 16 shows a top view of a power module 100 according to other embodiments of the utility model, and fig. 15 is a view along a section B-B of fig. 16. Referring to fig. 15 and 16, the power module 100 of fig. 15 is similar to the power module 100 of fig. 1, except that the power module 100 of fig. 15 further includes a housing 195. The housing 195 surrounds the base plate 160, and the first and second terminals 182, 184 are located on the housing 195. The first terminal 182 is electrically connected to the source pattern 112S through the wire bond 156, and the second terminal 184 is electrically connected to the drain pattern 112D through the wire bond 158. In addition, the power module 100 of fig. 15 includes a fourth terminal 188 and a gate pattern 112G1. The fourth terminal 188 is on the housing 195, and the fourth terminal 188 is electrically connected to the gate pattern 112G1 through the wire 159. The fourth terminal 188 is electrically connected to the gate pattern 112G through a bridge 189. The bridge 189 is a conductor and contacts only the gate patterns 112G and 112G1. Therefore, the fourth terminal 188 is not electrically connected to the source pattern 112S and the drain pattern 112D. It should be noted that the bridge 189 is omitted from fig. 8 for simplicity of the drawing. A voltage may be provided from the fourth terminal 188 to the gate 126 of the chip 120 to turn on the chip in the power module 100, such that the source 122 and the drain 124 of the chip have a potential difference. Current may flow along the second terminal 184 through the drain pattern 112D, the drain 124 of the chip 120, the source 122 of the chip 120, the support post 130, the heat spreader 140, the bonding body 152, the source pattern 112S to the first terminal 182.

Fig. 17 shows a top view of a power module 100 according to further embodiments of the utility model. The power module 100 of fig. 17 is similar to the power module 100 of fig. 16, except that the joint 152 of the power module 100 of fig. 17 is a plurality of ribbons, and the width of the ribbons is between 1 mm and 2 mm.

Fig. 18 shows a top view of a power module 100 according to further embodiments of the present utility model. The power module 100 of fig. 18 is similar to the power module 100 of fig. 17, except that the power module 100 of fig. 18 may have a third terminal 186 that is pin-shaped.

Table 1 shows the joint strength of the joints at different positions in some embodiments of the present utility model, using 380 μm aluminum wire as the joint. Referring to fig. 2 and table 1, in particular, when the bonding body 152 is located above the chips 120 or when the bonding body 152 is located above the gap G between the chips 120, the magnitude of the pushing force that can remove the bonding body 152 from the surface of the heat dissipation plate 140 is not greatly different. The joint body 152 is pushed away by a horizontal pushing force from the joint of the joint body 152 and the heat dissipation plate 140. That is, the maximum thrust force that the bond 152 above the chips 120 can withstand is similar to the bond 152 above the gap G between the chips 120. In addition, the material remaining area of the contact is greater than 80% when the bond 152 is removed, either the bond 152 above the die 120 or the bond 152 above the gap G between the dies 120. This means that the strength of the joint itself is sufficient so that the material of the joint remains on the heat sink 140 even after the joined body 152 is removed. Therefore, the strength of the joints is similar whether the joints 152 are above the chips 120 or the joints 152 are above the gaps G between the chips 120.

TABLE 1

Fig. 19 illustrates a cross-sectional view of a power module 100 according to further embodiments of the present utility model. Fig. 20 is a top view of a power module 100 according to other embodiments of the present utility model, and fig. 19 is a view along a section C-C of fig. 20. Referring to fig. 19 and 20, the power module 100 of fig. 19 is similar to the power module 100 of fig. 2, except that the power module 100 of fig. 19 includes a bond body, and the bond body includes a metal post 200 and bonding materials 202, 204. The metal pillar 200 connects the heat spreader 140 and the trace layer 112. In some embodiments, the heat spreader 140 extends above the source pattern 112S of the trace layer 112, and the bonding material 202 is electrically connected to the heat spreader 140 and the metal pillar 200, and the bonding material 204 is electrically connected to the source pattern 112S and the metal pillar 200.

Fig. 21 illustrates a cross-sectional view of a power module 100 according to further embodiments of the present utility model. The power module 100 of fig. 21 is similar to the power module 100 of fig. 19, except that the heat spreader plate 140 of the power module 100 of fig. 21 further includes a groove structure 142, the groove structure 142 being on the support post 130. The groove structure 142 can be used to reduce thermal stress caused by thermal expansion and contraction. For example, when the power module 100 emits heat due to the operation of the chip 120, the groove structure 142 can provide a space for heat expansion and cold contraction, so that the thermal stress of the heat dissipation plate 140 is reduced.

Fig. 22 shows a cross-sectional view of a power module 100 according to further embodiments of the utility model. Fig. 23 shows a top view of a power module 100 according to other embodiments of the utility model, and fig. 22 is a view along a section D-D of fig. 23. Referring to fig. 22 and 23, the power module 100 of fig. 22 is similar to the power module 100 of fig. 19, except that the metal pillars 200 and the bonding material 202 are removed from the power module 100 of fig. 22, and the bonding material 204 is used as a bonding body to connect the heat dissipation plate 140 and the trace layer 112. The heat spreader 140 is concavely folded toward the trace layer 112, and the bonding material 204 directly connects the heat spreader 140 and the trace layer 112.

Fig. 24 illustrates a cross-sectional view of a power module 100 according to further embodiments of the present utility model. The power module 100 of fig. 24 is similar to the power module 100 of fig. 22, except that the heat spreader plate 140 of the power module 100 of fig. 24 further includes a groove structure 142, the groove structure 142 being on the support post 130. The groove structure 142 can be used to reduce thermal stress caused by thermal expansion and contraction. For example, when the power module 100 emits heat due to the operation of the chip 120, the groove structure 142 can provide a space for heat expansion and cold contraction, so that the thermal stress of the heat dissipation plate 140 is reduced.

Fig. 25 shows a cross-sectional view of a power module 100 according to further embodiments of the present utility model. The power module 100 of fig. 25 is similar to the power module 100 of fig. 22, except that the heat dissipation plate 140 of the power module 100 of fig. 25 is concavely folded toward the trace layer 112, and a portion of the concavely folded heat dissipation plate 140 extends along the trace layer 112.

Fig. 26 shows a cross-sectional view of a power module 100 according to further embodiments of the utility model. The power module 100 of fig. 26 is similar to the power module 100 of fig. 25, except that the heat spreader plate 140 of the power module 100 of fig. 26 further includes a groove structure 142, the groove structure 142 being on the support post 130. The groove structure 142 can be used to reduce thermal stress caused by thermal expansion and contraction. For example, when the power module 100 emits heat due to the operation of the chip 120, the groove structure 142 can provide a space for heat expansion and cold contraction, so that the thermal stress of the heat dissipation plate 140 is reduced.

In summary, the power module according to some embodiments of the present utility model has the advantages of low stress accumulation, high reliability, high current uniformity, and high heat dissipation. Specifically, the support posts and the bonding material can act as buffers to reduce stress build-up between the bonding material and the chip. Since the heat spreader plate does not extend to and bond with the trace layer, the thermal expansion coefficient mismatch and thermal stress accumulation problems between materials due to the elevated temperature in the bonding process (e.g., solder or silver sintering process) are relatively small. In addition, since the bonding bodies are densely distributed on the heat dissipation plate, each bonding body can uniformly distribute the current flowing to the source electrode of the chip, thereby achieving the purpose of uniform current. The heat emitted by the chip during operation can be emitted upwards along the support column and through the heat dissipation plate. Since the heat transferred upward has been partially dissipated from the heat dissipation plate, the heat transferred to the joined body is small, and thermal stress is not easily generated in the joined body. Thus, the reliability of the power module can be improved.

The foregoing is only some, but not all, embodiments of the present utility model, and any equivalent modifications of the technical solution of the present utility model will be covered by the claims of the present utility model by a person of ordinary skill in the art from reading the description of the present utility model.

[ symbolic description ]

100: power module

110: substrate board

112: wiring layer

112D: drain electrode pattern

112G, 112G1: gate pattern

112S: source electrode pattern

114: insulating layer

116: conductor layer

120: chip

121: semiconductor layer

122: source electrode

124: drain electrode

126: grid electrode

130: support column

140: heat radiation plate

140H: holes and holes

142: groove structure

152: joint body

154. 156, 158, 159: wire bonding

160: bottom plate

172. 173, 174, 176, 178, 202, 204: bonding material

182: first terminal

184: second terminal

186: third terminal

188: fourth terminal

189: bridge span

190: packaging adhesive

195: outer casing

200: metal column

A-A, A '-A', A '-A', B-B, C-C, D-D: cross section of

G: gap of

P1: path

P2: path

W1: wire diameter

W2: width of the material.

Claims (10)

1. A power module, comprising:

a substrate including a wiring layer;

a plurality of chips located on the wiring layer of the substrate, wherein any one of the chips comprises a source electrode, a drain electrode and a grid electrode;

a plurality of support columns located on the plurality of chips;

a heat dissipation plate located on and connected to the plurality of support columns; and

and a plurality of joints connecting the heat dissipation plate and the wiring layer.

2. The power module of claim 1, wherein the plurality of chips have gaps therebetween, and the plurality of bond bodies are located on the heat sink and directly above the plurality of chips and the gaps at the same time.

3. The power module of claim 1, wherein the plurality of joints are a plurality of wires or a plurality of ribbons.

4. The power module of claim 1, wherein any one of the plurality of support posts connects the source of any one of the plurality of chips with the heat sink.

5. The power module of claim 1, further comprising a plurality of wires on the plurality of chips and connected to the trace layer, wherein the trace layer further comprises:

a drain pattern on which the plurality of chips are disposed, and to which the drain of any one of the plurality of chips is connected;

a source pattern adjacent to and separated from the drain pattern, wherein the plurality of joints connect the source pattern and the heat dissipation plate; and

and a gate pattern adjacent to and separated from the drain pattern, wherein the plurality of wires connect the gate pattern with the gate of any one of the plurality of chips.

6. The power module of claim 5, further comprising:

a first terminal connected to the source pattern;

a second terminal connected to the drain pattern; and

and a fourth terminal connected to the gate pattern.

7. The power module of claim 1, wherein the trace layer further comprises:

a source pattern, wherein the plurality of chips are disposed on the source pattern, and the source of any one of the plurality of chips is connected to the source pattern;

a drain pattern adjacent to and separated from the source pattern, wherein the plurality of joints connect the drain pattern and the heat dissipation plate; and

and a gate pattern adjacent to and separated from the source pattern, wherein the gate pattern connects the gate of any one of the plurality of chips.

8. The power module of claim 1, wherein the plurality of bond bodies are a plurality of metal posts or a plurality of bond materials.

9. The power module of claim 1 wherein the heat spreader plate includes a recessed structure on the plurality of support posts.

10. The power module of claim 1, wherein the heat spreader is concavely folded toward the trace layer, and a portion of the concavely folded heat spreader extends along the trace layer.

Images