阅读说明：本技术 微流制冷通道的制作方法以及芯片 (Method for manufacturing micro-flow refrigeration channel and chip ) 是由 黄立 马占锋 高健飞 黄晟 王春水 叶帆 于 2021-06-24 设计创作，主要内容包括：本发明涉及一种微流制冷通道的制作方法,包括：在待制冷基材上形成牺牲层；根据微流制冷通道的设计形状,图形化牺牲层；在牺牲层上沉积盖面层；释放牺牲层,盖面层立于待制冷基材上并与待制冷基材围设形成微流制冷通道。另外还涉及基于该方法集成有微流制冷通道的芯片。本发明采用MEMS微加工工艺将微流制冷通道集成在待制冷基材上,工艺简单、易于实现,适于与传统的半导体工艺兼容,芯片与通道材料之间不会产生内应力、粘附力等以及不会对芯片造成电学等影响,保持芯片的正常功能和性能。制作的微流制冷通道更贴近发热源,能实现针对性地制冷设计,制冷效果可靠、能耗低,所需的空间较小,能较好地满足芯片制冷要求。(The invention relates to a method for manufacturing a micro-flow refrigeration channel, which comprises the following steps: forming a sacrificial layer on a substrate to be cooled; patterning the sacrificial layer according to the design shape of the micro-flow refrigeration channel; depositing a cover surface layer on the sacrificial layer; and releasing the sacrificial layer, wherein the cover surface is erected on the base material to be refrigerated and is surrounded with the base material to be refrigerated to form a micro-flow refrigeration channel. The chip integrated with the micro-flow refrigeration channel based on the method is also disclosed. The micro-flow refrigeration channel is integrated on the base material to be refrigerated by adopting the MEMS micro-processing technology, the technology is simple, the realization is easy, the micro-flow refrigeration channel is compatible with the traditional semiconductor technology, the internal stress, the adhesive force and the like can not be generated between the chip and the channel material, the electricity and other influences on the chip can not be caused, and the normal function and the performance of the chip can be maintained. The manufactured micro-flow refrigeration channel is closer to a heating source, the targeted refrigeration design can be realized, the refrigeration effect is reliable, the energy consumption is low, the required space is smaller, and the chip refrigeration requirement can be better met.)

1. A method of fabricating a microfluidic cooling channel, comprising:

s1, forming a sacrificial layer on the substrate to be cooled;

s2, patterning the sacrificial layer according to the design shape of the micro-flow refrigeration channel;

s3, depositing a cover layer on the sacrificial layer;

and S4, releasing the sacrificial layer, wherein the cover surface is erected on the base material to be refrigerated and forms a micro-flow refrigeration channel with the base material to be refrigerated in an enclosing manner.

2. The method of making a microfluidic cooling channel according to claim 1, wherein: the cover surface layer is formed by depositing silicon nitride, silicon carbide or silicon oxynitride.

3. The method of making a microfluidic cooling channel according to claim 1, wherein: the sacrificial layer is made of silicon-based sacrificial materials, carbon-based sacrificial materials or polyimide sacrificial materials.

4. A method of making a microfluidic cooling channel as claimed in claim 3, wherein:

when the sacrificial layer is made of a silicon-based sacrificial material, in S4, releasing the sacrificial layer by an acid corrosion method;

when the sacrificial layer is made of a carbon-based sacrificial material or a polyimide sacrificial material, in S4, the sacrificial layer is released in an oxygen high-temperature reaction or an oxygen microwave manner.

5. The method of making a microfluidic cooling channel according to claim 1, wherein: and S2, after the sacrificial layer is patterned, cleaning to remove the photoresist and the etching slag.

6. The method of making a microfluidic cooling channel according to claim 1, wherein: the thickness of the sacrificial layer is 6-20 mu m.

7. The method of making a microfluidic cooling channel according to claim 1, wherein: the base material to be cooled is a chip wafer.

8. A chip, including chip wafer, its characterized in that: the method for manufacturing the micro-flow refrigeration channel as claimed in any one of claims 1 to 6 is adopted to integrate the micro-flow refrigeration channel on a chip wafer.

Technical Field

The invention belongs to the technical field of chip refrigeration, and particularly relates to a manufacturing method of a micro-flow refrigeration channel and a chip integrated with the micro-flow refrigeration channel based on the manufacturing method.

Background

With the rapid development of semiconductor technology, high integration miniaturization has become one of the most important development directions of electronic products. Nowadays, in electronic products, transistors for controlling current and storing information are getting smaller and smaller, the number of transistors integrated in a unit chip area is getting larger and larger, and the application of chips is limited by the high heat generated therewith.

In order to prevent the electronic product, i.e. the chip, from overheating and maintain its application with high efficiency and long service life, the conventional chip generally adopts a liquid cooling or air cooling heat dissipation method, such as a circulating water cooling device or a fan air cooling device, etc. adopted in a large host system or a computer. However, both conventional liquid cooling and air cooling techniques have their own disadvantages: the liquid cooling technique needs to consume a large amount of water resources; the air cooling technology is difficult to obtain reliable refrigeration effect, noise is generated, and extra electric power is consumed; meanwhile, the cooling devices occupy larger volume space, which is a great disadvantage for high-integration miniaturized products.

Chinese patent CN109524373A discloses a three-dimensional active heat dissipation package structure of an embedded micro channel and a manufacturing process thereof, which integrates a micro channel structure with a size at a micron level on the back of a functional chip, introduces a coolant to take away heat generated in an active region of the chip, and can improve the heat dissipation effect of the chip; the micro-channel structure is formed by directly etching the back of the chip and then bonding the micro-channel cover plate on the back of the chip, on one hand, the method needs thicker chip thickness and correspondingly increases the production cost, on the other hand, the problems of high operation cost, high operation difficulty and the like exist in the chip etching, and the bonding connection reliability between the micro-channel cover plate and the chip is difficult to guarantee.

Disclosure of Invention

The invention relates to a manufacturing method of a micro-flow refrigeration channel and a chip integrated with the micro-flow refrigeration channel based on the manufacturing method, which can at least solve part of defects in the prior art.

The invention relates to a method for manufacturing a micro-flow refrigeration channel, which comprises the following steps:

s1, forming a sacrificial layer on the substrate to be cooled;

s2, patterning the sacrificial layer according to the design shape of the micro-flow refrigeration channel;

s3, depositing a cover layer on the sacrificial layer;

and S4, releasing the sacrificial layer, wherein the cover surface is erected on the base material to be refrigerated and forms a micro-flow refrigeration channel with the base material to be refrigerated in an enclosing manner.

As an embodiment, the cap layer is formed by deposition of silicon nitride, silicon carbide or silicon oxynitride.

In one embodiment, the sacrificial layer is made of a silicon-based sacrificial material, a carbon-based sacrificial material, or a polyimide-based sacrificial material.

In one embodiment, when the sacrificial layer is made of a silicon-based sacrificial material, in S4, the sacrificial layer is released by an acid etching method;

when the sacrificial layer is made of a carbon-based sacrificial material or a polyimide sacrificial material, in S4, the sacrificial layer is released in an oxygen high-temperature reaction or an oxygen microwave manner.

As one embodiment, in S2, after patterning the sacrificial layer, the photoresist and the etching residue are cleaned and removed.

In one embodiment, the thickness of the sacrificial layer is 6 to 20 μm.

As an embodiment, the substrate to be cooled is a chip wafer.

The invention also relates to a chip which comprises a chip wafer, wherein the microfluidic refrigeration channel is integrated on the chip wafer by adopting the manufacturing method of the microfluidic refrigeration channel.

The invention has at least the following beneficial effects:

the micro-flow refrigeration channel is integrated on the base material to be refrigerated by adopting the MEMS micro-processing technology, the technology is simple, the realization is easy, the micro-flow refrigeration channel is compatible with the traditional semiconductor technology, the internal stress, the adhesive force and the like can not be generated between the chip and the channel material, the electricity and other influences on the chip can not be caused, and the normal function and the performance of the chip can be maintained. The manufactured micro-flow refrigeration channel is closer to a heating source, the targeted refrigeration design can be realized, the refrigeration effect is reliable, the energy consumption is low, the required space is smaller, and the chip refrigeration requirement can be better met.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1-4 are schematic views illustrating a manufacturing process of a micro-flow cooling channel according to an embodiment of the present invention; wherein, fig. 1 is a schematic view of the step S1, fig. 2 is a schematic view of the step S2, fig. 3 is a schematic view of the step S3, and fig. 4 is a schematic view of the step S4;

FIG. 5 is a schematic view of a microfluidic cooling channel according to an embodiment of the present invention;

fig. 6-9 are schematic views illustrating a process for fabricating another micro-fluidic cooling channel (a micro-fluidic cooling channel is formed on a substrate) according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

Referring to fig. 1 to 4, an embodiment of the present invention provides a method for manufacturing a micro-flow refrigeration channel, including:

s1, forming a sacrificial layer 2 on the substrate 1 to be cooled;

s2, patterning the sacrificial layer 2 according to the design shape of the micro-flow refrigeration channel 4;

s3, depositing a cover layer 3 on the sacrificial layer 2;

and S4, releasing the sacrificial layer 2, and erecting the cover surface layer 3 on the substrate 1 to be refrigerated and enclosing the substrate 1 to be refrigerated to form a micro-flow refrigeration channel 4.

In this embodiment, one of the purposes is to integrate the micro-flow cooling channel 4 on a chip, and the substrate 1 to be cooled may be a chip wafer; of course, the material of the substrate 1 is not limited to the one, and the micro-flow cooling channel 4 manufactured by the above method is obviously also suitable for cooling other devices, which is not exemplified here.

When the substrate 1 to be cooled is a chip wafer, the microfluidic cooling channel 4 can be fabricated after the chip wafer completes basic functional processing, so as to avoid damage to the cover layer 3 and the like caused by the integration of the microfluidic cooling channel 4 and the subsequent basic functional processing.

Preferably, in S1, the sacrificial layer 2 is made of silicon-based sacrificial material, carbon-based sacrificial material or polyimide-based sacrificial material, and these sacrificial materials have well-established sacrificial release technology. Preferably, when the sacrificial layer 2 is made of a silicon-based sacrificial material, in S4, the sacrificial layer 2 is released by an acid etching method; when the sacrificial layer 2 is made of a carbon-based sacrificial material or a polyimide sacrificial material, in S4, the sacrificial layer 2 is released by an oxygen high-temperature reaction or an oxygen microwave method.

For the arrangement of the sacrificial layer 2, a mode of coating the sacrificial layer 2 material on the base material 1 can be adopted. The thickness of the sacrificial layer 2 can be determined according to the design depth of the micro-flow refrigeration channel 4, and the like, and in this embodiment, the thickness of the sacrificial layer 2 can be between 6 μm and 20 μm, and is further preferably controlled between 10 μm and 20 μm.

Further optimizing the above method, in S2, the sacrificial layer 2 is patterned by conventional techniques, and in one embodiment, the sacrificial layer 2 is patterned by semiconductor etching. Specifically, as shown in fig. 2 and 3, the patterned sacrificial layer 2 includes a protrusion structure and a sink structure; the shape of the convex structure is the same as that of the micro-flow refrigeration channel 4 (the number and the layout of the convex blocks are the same as that of the micro-flow channels of the micro-flow refrigeration channel 4, the height of the convex blocks is the same as the depth of the micro-flow channels, and the width of a single convex block is the same as that of the micro-flow channels), when the cover surface layer 3 is deposited, the convex structure plays a role in supporting and shaping, and when the convex structure is released, the supported cover surface material can enclose with the substrate 1 to form the micro-flow channels; the depth of the sink groove structure is preferably the same as the height of the sacrificial layer 2, that is, when the sacrificial layer 2 is patterned, the etching depth is the same as the height of the sacrificial layer 2, when the cover layer 3 is deposited, the cover material can be directly deposited on the substrate 1 at the sink groove structure, on one hand, the support of the cover layer 3 on the substrate 1 can be realized to be stable, and on the other hand, the non-set streaming between adjacent microchannels can be avoided.

In one embodiment, as shown in fig. 5, the micro-fluidic cooling channel 4 has a serpentine shape, and the sacrificial layer 2 is patterned accordingly.

The cover surface layer 3 has the requirement that the sacrificial layer 2 still can stand on the substrate 1 after being released, and meanwhile, the cover surface layer and the substrate 1 need to be enclosed to form a micro-flow refrigeration channel 4, so that the micro-flow refrigeration channel 4 is ensured to allow the flow to meet the requirement of the chip refrigeration capacity, and therefore, the cover surface layer 3 is preferably made of a material with stable selection performance and structure; in one embodiment, the cap layer 3 is formed by deposition of silicon nitride, silicon carbide or silicon oxynitride.

The deposition of the facing layer 3 is a conventional technique, the thickness of the facing layer 3 can be limited according to specific conditions, and in one embodiment, the thickness of the facing layer 3 is in the range of 8-10 μm, which can ensure the structural strength and the operational reliability of the facing layer 3.

Further preferably, in S2, after the sacrificial layer 2 is patterned, the photoresist and the etching slag are cleaned and removed to ensure the deposition effect and the operational reliability of the cover layer 3.

Preferably, when the substrate 1 is a chip wafer, the cover surface layer 3 is collectively packaged during packaging of the chip wafer, so that the cover surface layer 3 can be protected well and the operational reliability of the micro-flow cooling channel 4 can be improved.

As a preferable scheme, as shown in fig. 6 to 9, on the basis of the formation of the micro-flow refrigeration channel 4, a micro-flow refrigeration channel 11 (for example, by etching) may be further formed on the substrate 1, the micro-flow refrigeration channel 11 and the micro-flow refrigeration channel 4 are arranged in a staggered manner, after the micro-flow refrigeration channel 4 is formed, the micro-flow refrigeration channel 11 and the micro-flow refrigeration channel 4 are connected end to end, for example, the micro-flow refrigeration channel 11 penetrates through one side wall of the substrate 1 to form a medium inlet, the outlet end of the micro-flow refrigeration channel 11 is communicated with the inlet end of the micro-flow refrigeration channel 4, and the outlet pipe of the micro-flow refrigeration channel 4 is formed as a medium outlet; based on the structure, the circulation length and the cooling area of the micro-flow refrigeration medium can be obviously increased, so that the cooling effect on the base material 1 is obviously improved, and the cooling process is more reliable. Before the micro-flow refrigeration channel 4 is manufactured, the micro-flow refrigeration channel 11 is etched and formed on the base material 1 in advance, then, when the sacrificial layer 2 is formed, the sacrificial material is filled in the micro-flow refrigeration channel 11, when the sacrificial layer 2 is released, the sacrificial material in the micro-flow refrigeration channel 11 is released together, and therefore a structure that the micro-flow refrigeration channel 4 is connected and communicated with the micro-flow refrigeration channel 11 is formed, the manufacturing is convenient, and the integration of a refrigeration channel formed by connecting and communicating the micro-flow refrigeration channel 4 and the micro-flow refrigeration channel 11 can be guaranteed. As shown in fig. 7-9, in order to ensure the support of the cover layer 3 to be stable, the width of the micro-flow groove of the micro-flow refrigeration channel 11 is smaller than the width of the sinking groove structure; meanwhile, as shown in fig. 8 and 9, the micro-flow refrigeration channel 11 can be closed through the cover layer 3 deposited in the sink structure without additionally arranging a cover plate, so that the operation is convenient, the material consumption can be saved, the manufacturing procedures can be reduced, and the closing reliability is high.

According to the manufacturing method of the micro-flow refrigeration channel, the micro-flow refrigeration channel 4 is integrated on the base material 1 to be refrigerated by adopting an MEMS micro-machining process, the process is simple and easy to realize, the manufacturing method is compatible with the traditional semiconductor process, the internal stress, the adhesive force and the like cannot be generated between the chip and the channel material, the influence on the chip such as electricity cannot be caused, and the normal function and performance of the chip can be maintained. The manufactured micro-flow refrigeration channel 4 is closer to a heating source, the targeted refrigeration design can be realized, the refrigeration effect is reliable, the energy consumption is low, the required space is smaller, and the chip refrigeration requirement can be better met.

Example two

The embodiment of the invention provides a chip which comprises a chip wafer, and the micro-flow refrigeration channel 4 is integrated on the chip wafer by adopting the manufacturing method of the micro-flow refrigeration channel provided by the embodiment I. The structure of the micro-flow cooling channel 4 is described in the first embodiment, and specifically includes:

as shown in fig. 4, the micro-flow refrigeration channel 4 is formed by enclosing a substrate 1 to be refrigerated and a cover surface layer 3 deposited on the substrate 1 to be refrigerated, the cover surface layer 3 comprises a cover surface platform deposited and overlapped on the surface of the substrate 1 to be refrigerated and a plurality of inverted U-shaped stacking platforms protruding from the cover surface platform and sequentially connected in series, the cover surface platform is correspondingly provided with a notch so that each inverted U-shaped stacking platform can be enclosed with the surface of the substrate 1 to be refrigerated to form a micro-flow channel, and each inverted U-shaped stacking platform is sequentially connected in series and communicated, so that each micro-flow channel is sequentially connected in series and communicated to form the micro-flow refrigeration channel 4. The facing platform and inverted U-shaped buttress described above are apparently formed by patterning of the sacrificial layer.

In one embodiment, as shown in fig. 5, the micro-flow refrigeration channels 4 are distributed in a serpentine shape, so that the retention time of the working medium can be prolonged, and the heat exchange area can be increased, thereby improving the refrigeration efficiency and effect.

The cover surface layer 3 needs to be suitable for standing on the substrate 1, and meanwhile, the cover surface layer needs to be enclosed with the substrate 1 to form a micro-flow refrigeration channel 4, so that the micro-flow refrigeration channel 4 is ensured to allow flow to meet the requirement of chip refrigerating capacity, and therefore, the cover surface layer 3 is preferably made of a material with stable selection performance and structure; in one embodiment, the cap layer 3 is formed by deposition of silicon nitride, silicon carbide or silicon oxynitride.

The thickness of the cover layer 3 can be limited according to specific conditions, and in one embodiment, the thickness of the cover layer 3 is in the range of 8-10 μm, so that the structural strength and the working reliability of the cover layer 3 can be ensured.

As a preferable scheme, as shown in fig. 6 to 9, on the basis of the formation of the micro-flow refrigeration channel 4, a micro-flow refrigeration channel 11 (for example, by etching) may be further formed on the substrate 1, the micro-flow refrigeration channel 11 and the micro-flow refrigeration channel 4 are arranged in a staggered manner, after the micro-flow refrigeration channel 4 is formed, the micro-flow refrigeration channel 11 and the micro-flow refrigeration channel 4 are connected end to end, for example, the micro-flow refrigeration channel 11 penetrates through one side wall of the substrate 1 to form a medium inlet, the outlet end of the micro-flow refrigeration channel 11 is communicated with the inlet end of the micro-flow refrigeration channel 4, and the outlet pipe of the micro-flow refrigeration channel 4 is formed as a medium outlet; based on the structure, the circulation length and the cooling area of the micro-flow refrigeration medium can be obviously increased, so that the cooling effect on the base material 1 is obviously improved, and the cooling process is more reliable. As shown in fig. 7-9, in order to ensure the support of the cover layer 3 to be stable, the width of the micro-flow groove of the micro-flow refrigeration channel 11 is smaller than the width of the sinking groove structure; meanwhile, as shown in fig. 8 and 9, the micro-flow refrigeration channel 11 can be closed by the cover layer 3 (i.e. the cover platform) deposited in the sink structure, no additional cover plate is needed, the operation is convenient, the material consumption can be saved, the manufacturing procedures can be reduced, and the closing reliability is high.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.