HOT/COLD TEST EQUIPMENT FOR NAND FLASH MEMORY WITH DEHUMIDIFYING FUNCTION

Abstract

Disclosed herein is hot/cold test equipment for a Nand Flash Memory. The test equipment includes a mounting unit that contains the Nand Flash Memory together with a socket to test whether the memory is defective or not, a chamber provided above the mounting unit and moving up and down to come into contact with the socket and thereby provide a target temperature, and a temperature display displaying the target temperature. The chamber includes a block inserted into the socket, a thermoelectric element seated on an upper portion of the block, a water jacket seated on an upper portion of the thermoelectric element and circulating cooling water therein, and a cooling fan provided in the water jacket to blow air downwards, with a discharge hole being formed on a lower surface of the block to discharge nitrogen gas.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to test equipment for Nand Flash Memory and, more particularly, to hot/cold test equipment with a dehumidifying function, capable of performing a cold test as well as a hot test.

2. Description of the Related Art

The most difficult problem with the semiconductor production process is the requirement for temperature test equipment that is accurate and rapid. To address this problem, there is an urgent need for temperature test equipment that can maximize productivity.

However, such test equipment incurs a problem related to high efficiency. Thus, in recent years, owing to developments in nano-technology made because of various studies, research into a thermoelectric element field capable of implementing clean energy is being actively conducted. Therefore, there is a need to develop temperature test equipment using the thermoelectric element at low cost with high efficiency.

Further, until now, a hot test was mainly performed but a cold test was not performed, as a temperature test. Therefore, people want to develop temperature test equipment capable of performing the cold test as well as the hot test while using the thermoelectric element.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide hot/cold test equipment using a thermoelectric element, which can moreover prevent humidity from occurring in a cold test.

In order to accomplish the above object, the present invention provides hot/cold test equipment for a Nand Flash Memory, including a mounting unit that contains the Nand Flash Memory together with a socket to test whether the memory is defective or not, a chamber provided above the mounting unit and moving up and down to come into contact with the socket and thereby provide a target temperature, and a temperature display displaying the target temperature, wherein the chamber includes a block inserted into the socket, a thermoelectric element seated on an upper portion of the block, a water jacket seated on an upper portion of the thermoelectric element and circulating cooling water therein, and a cooling fan provided in the water jacket to blow air downwards, with a discharge hole being formed on a lower surface of the block to discharge nitrogen gas.

Further, the present invention provides hot/cold test equipment for a Nand Flash Memory, including a mounting unit that contains the Nand Flash Memory together with a socket to test whether the memory is defective or not, a chamber provided above the mounting unit and moving up and down to come into contact with the socket and thereby provide a target temperature, and a temperature display displaying the target temperature, wherein the chamber includes a block inserted into the socket, a thermoelectric element seated on an upper portion of the block, a heat pipe seated on an upper portion of the thermoelectric element, a radiator seated on an upper portion of the heat pipe, and a radiation fan disposed above the radiator to blow air downwards.

The block may be elastically supported in the chamber.

Further, the socket may include an adapter with which a lower end of the block comes into contact, and pinholes may be preferably formed in a bottom of the adapter to cause pins of the socket to protrude towards the block, come into contact with an interface of the Nand Flash Memory pressed by the block and then provide various electrical characteristics, when the block is pressed against the adapter.

The hot/cold test equipment may further include a nitrogen generator provided under the mounting unit to supply the nitrogen gas to the discharge hole.

Further, preferably, the block may include an upper block that comes into contact with a lower portion of the thermoelectric element, and a lower block that is coupled to a lower portion of the upper block and is inserted into the socket, and the heat pipe may be provided between the upper block and the lower block, and a temperature sensor may be provided in an interior adjacent to a bottom of the lower block to be connected to the temperature display.

Furthermore, outer portions of the block and the thermoelectric element may be surrounded by an insulator.

Further, a wick made of copper may be provided in the heat pipe in such a way as to extend from an evaporation portion to a middle portion of the heat pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view showing test equipment according to the present invention;

FIG. 2 is a front view showing the test equipment of FIG. 1;

FIG. 3 is a detailed view showing a socket of FIG. 1;

FIG. 4 is a view showing an interior of a chamber for a cold test;

FIG. 5 is a view showing an interior of a chamber for a hot test;

FIG. 6 is a view showing the test equipment according to the present invention, in which it further includes a nitrogen generator;

FIG. 7 is a view showing an inner structure of a heat pipe used in the present invention; and

FIG. 8 is a sectional view showing a portion having a wick in FIG. 7.

DESCRIPTION OF PREFERRED EMBODIMENTS

Hereinafter, hot/cold test equipment for Nand Flash Memory with a dehumidifying function according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Referring to FIGS. 1 and 2, hot/cold test equipment 100 according to the present invention includes a mounting unit 110, a chamber 130 and a temperature display 160 in the order of going from a lower position to an upper position.

The mounting unit 110 contains the Nand Flash Memory to be tested, and applies electricity to the memory to determine whether the memory is defective or not. A plurality of sockets 115 is mounted on an upper surface of such a mounting unit 110, and memories are put into the corresponding sockets 115.

The chamber 130 above the mounting unit 110 moves along vertical guides 120 downwards to the mounting unit 110 to be in close contact therewith, or upwards from the mounting unit 110 to be spaced apart therefrom. A function of the chamber 130 is to apply heat or take heat away from the memory so that it is in a hot or cold state. In order to move the chamber 130 up and down, as shown in FIG. 2, a vertical rack gear 150 may pass through a rear portion of the chamber 130, and a gear (not shown) may be provided in the chamber 130 to engage with the rack gear 150. The reason why the hot or cold state is thus provided to the memory is because the memory is checked to be normally operated in an extreme situation so as to increase the reliability of a test.

The temperature display 160 individually displays the temperature provided to respective memories by the number of the memories to be tested.

As shown in FIG. 3, each socket 115 mounted on the mounting unit 110 has a concave adapter 116, and a plurality of pinholes 117 is formed in a bottom of the adapter 116 in such a way that pins protrude from the socket 115. That is, the adapter 116 is elastically mounted from below. Thus, if an adapter side is pushed a little, the adapter 116 moves down while the pins protrude through the pinholes 117. Since the pins protrude through the pinholes 117 into the adapter 116, the pins connect the test memory to a block and thereby a precise test can be advantageously carried out using direct heat transfer. This is differentiated from a conventional method wherein the test is carried out using indirect heat transfer between the block and the memory that occurs through the ambient air.

The chamber 130 according to the present invention can be used for both the hot test and the cold test. Another chamber is provided to be used only for the hot test.

First, the chamber for the hot test or the cold test utilizes a thermoelectric element in common. This thermoelectric element will be described below.

The thermoelectric element is a new generation cooling substrate which can simultaneously perform a cooling operation, a heating operation, a constant temperature maintaining operation, and a power generating operation using just the supply of DC power with a thermoelectric material, and can ensure convenient and reliable exchange between heat and electricity. This thermoelectric element is used as a substitute for a conventional cooling method that uses a compressor, thus enabling both the cooling operation and the heat emitting operation to be conveniently performed anytime and anywhere. Thereby, according to the application of technology, in the case of the best specification, the temperature of a product can be freely adjusted and kept constant from between −75° C. to a maximum of +300° C. with an accuracy of ±0.03° C. In addition, it is an element that can carry out the cooling operation and the heating operation as soon as it is attached to a portion ranging from a small portion of 0.8 cm wide×0.8 cm long to a wide portion, is an environment-friendly product which breaks with the use of Freon gas and has higher quality than the products of other companies because it is more convenient and precise.

If an on-off control method is used in the case of making a system using such a thermoelectric element, this has a fatal effect on the life span of the thermoelectric element, so that a product using “GM attachment technology” needs to be utilized. That is, in the case of implementing a real system, it is difficult to selectively use only one of the cooling operation and the heating operation. Therefore, according to the present invention, a special product using “GM attachment technology” is utilized as the thermoelectric element, thus remarkably improving durability.

Further, since the thermoelectric element is made of ceramic, it frequently breaks down if the tightening force is excessive or is non-uniform at four corners when assembling a cooling unit. Thus, a lot of care is required to assemble the thermoelectric element. A product made of thin ceramic may be easily destroyed by external shock, and in addition, may be broken even by external shocks during assembly.

Mechanical destruction of the thermoelectric element that is most widely known occurs when assembling the cooling unit. Thus, in order to solve the problem, the present invention integrates the “GM attachment technology” into the thermoelectric material to remarkably improve the strength of the material. The test results are shown in the following Table 1.

	TABLE 1
	electrical shock durability
	test [40/90 test]
		number of	mechanical
	time required	experiments	shock test
thermoelectric	for element	on element	number of shocks
element specification	destruction	destruction	[just before
HMN 6040 standard	[Time]	[Cycle]	destruction]
before improvement	49.2	649	352
application of	3,795	45,002	7,756
GM attachment
technology

As shown in FIG. 4, the hot/cold combination chamber 130 according to the present invention is provided with blocks 131 which are inserted into the adapters 116 of the corresponding sockets 115 so as to be put in close contact therewith. Thermoelectric elements 132 are seated on upper surfaces of the respective blocks 131, and a water jacket 133 is seated on the upper surface of the thermoelectric elements 132 to move cooling water therein. Also, a cooling fan 134 is provided in the water jacket 133. The blocks 131 and the water jacket 133 are elastically supported at upper and lower portions thereof by vertical rods 139 that are provided on opposite sides of the blocks 131 and the water jacket 133. That is, the blocks 131 and the water jacket 133 are elastically supported by springs 139a so as to mitigate shocks and adjust a contact force of the block 131, when the chamber 130 moves downwards so that each block 131 makes contact with the socket 115.

Such a block 131 includes an upper block 131a that makes contact with a lower portion of the thermoelectric element 132, and a lower block 131b that is located under the upper block 131a to be inserted into the socket 115. Further, in order to efficiently perform heat transfer between the upper block 131a and the lower block 131b, a heat pipe 180 extends integrally from an interior of the upper block 131a to a lower end of the lower block 131b. Furthermore, a temperature sensor hole 136 is formed in the lower block 131b, with a temperature sensor 137 disposed on a lower end of the temperature sensor hole 136. That is, the temperature sensor 137 is placed adjacent to the lower end of the lower block 131b, so that the temperature sensor 137 detects the temperature of the lower end of the lower block 131b and delivers it to the temperature display 160.

Further, a plurality of discharge holes 138 is formed in a lower surface of the lower block 131b. These discharge holes 138 inject nitrogen gas through the lower block 131b towards the socket 115, thus preventing humidity from occurring when performing the cold test. Thus, the discharge holes 138 extend upwards from the lower surface of the lower block 131b and then pass through both sides of the upper block 131a to be connected to a nitrogen generator that is on the exterior.

The water jacket 133 is a means for supplying cold air to the block 131, and blows the cold air, generated while circulating the cooling water, towards the block 131 using the cooling fan 134. The reason why the cold air is blown like this is because it takes a long time to reach a target temperature using just the thermoelectric element 132 and it is easier to reach the target temperature if the cold air is blown together. Further, in order to efficiently control the heat, an insulator 132a is installed outside the thermoelectric element 132. For reference, reference numeral “130a” denotes a steel plate body of the chamber 130.

As shown in FIG. 5, the chamber for the hot test is provided with blocks 141 that are inserted into the adapters 116 of the sockets 115 to come into close contact therewith. Thermoelectric elements 142 are seated on upper surfaces of respective blocks 141, and a heat pipe 180 is seated over the upper surfaces of the thermoelectric elements 142, with a radiator 143 and radiation fans 144 seated on an upper surface of the heat pipe 180. Further, each block 141 and each thermoelectric element 142 are surrounded by an insulator 148 to prevent heat from leaking. Furthermore, each block 141 includes an upper block 141a that is disposed just under the thermoelectric element 142, and a lower block 141b that is disposed under the upper block 141a to be inserted into the socket 115. Like the hot/cold combination chamber 130, a temperature sensor hole 146 is formed in the lower block 141b, and a temperature sensor 147 is inserted into the lower end of the temperature sensor hole 146. Thus, the temperature sensor 147 detects a temperature of the lower end of the block 141 and delivers it to the temperature display 160.

The reason why the heat pipe 180, the radiator 143 and the radiation fan 144 are separately provided above the thermoelectric element 142 is because this arrangement allows the target temperature to be more rapidly reached. In other words, it takes a long time to reach the target temperature using just the thermoelectric element 142. However, if heat is emitted using the heat pipe 180 and is transferred to pins of the radiator 143 and the radiation fan 144 blows hot air downwards, it is easy to reach the target temperature of each block 141.

In the drawing that shows the chamber 140 for the hot test, internal components such as the blocks 141 are not illustrated as being elastically supported like in the chamber 130 for the cold test. However, it is to be understood that the internal components can be elastically supported as shown in FIG. 4, although that is not described in detail.

The test equipment 100 according to the present invention may further include a nitrogen generator. Nitrogen used in the cold test can be supplied from a location where the equipment is installed. However, if the nitrogen is not supplied smoothly, the nitrogen generator may be added to the test equipment 100 itself.

As shown in FIG. 6, the nitrogen generator is installed to be disposed under the mounting unit 110. Such a nitrogen generator 170 supplies only high-purity nitrogen gas of 99.999% or more with unnecessary gases such as O₂, H₂O, and CO₂ being removed from the air using a carbon molecular sieve (CMS).

Since the CMS has high heat resistance, a wide specific surface area, and pore determining properties of a mesh structure, the CMS maintains a predetermined absorptivity even in the air that is low in water content, and thereby is suitable for applications in which the ultra-drying of the air is required. Further, the CMS has a specific surface area of 480 m²/g, a water adsorption capacity up to about 22%, and a regeneration temperature of about 200° C. to 320° C. The CMS is classified into CMS for air and CMS for gas, according to the characteristics of a product.

Meanwhile, the heat pipe 180 used in the present invention has a special structural shape to ensure good heat transfer. That is, as shown in FIGS. 7 and 8, an evaporation cap 181 is mounted to one end of the heat pipe 180, while a condensation cap 182 is mounted to the other end of the heat pipe 180. Further, a wick 185 is provided in the heat pipe 180 in such a way as to extend from the evaporation cap 171 to a middle portion of the heat pipe 180. As shown in FIG. 8, the wick 185 is made of copper, and is fitted into the heat pipe 180 in such a way as to be in close contact with an inner surface of the heat pipe 180, thus maximizing the evaporation and insulation of the heat pipe 180.

A specific example of the heat pipe 180 will be proposed in the following. However, the heat pipe is not limited thereto.

TABLE 2
Specification of Heat Pipe
	component	dimension (mm)	material
	wick	length 450	copper
		mesh 180
		thickness 0.02
	heat pipe	outer diameter 9.52	copper
		inner diameter 7.74
		thickness 0.89
		length 1200
	working fluid	purity (%) 99.9	water 5% (Vt)
			methanol 7.5% (Vt)
			total 12.5% (Vt)

The heat pipe 180 according to the present invention is manufactured so that its evaporation portion is 410 mm, its insulation portion is 180 mm, and its condensation portion is 610 mm to create an overall length of 1,200 mm. That is, when seeing an approximate ratio, the condensation portion is about a half of the entire heat pipe 180, and the insulation portion is about half as long as the evaporation portion. Thus, in the evaporation portion, a refrigerant is supplied with heat and is heated, so that the refrigerant is evaporated and vapor particles move towards the condensation portion at an acoustic velocity. Further, in the condensation portion, the vapor emits condensation heat so that it becomes liquid, and the liquid is returned by capillary force of the wick 185.

As described above, the present invention provides test equipment, which enables Nand Flash Memory to be tested in both a hot state and a cold state and thereby checks adaptability for various environments, thus enhancing the reliability of determining whether a product is defective or not.

Further, the present invention provides test equipment, which can suppress the humidity that may occur in a cold test.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

1. Hot/cold test equipment for a Nand Flash Memory, comprising a mounting unit that contains the Nand Flash Memory together with a socket to test whether the memory is defective or not, a chamber provided above the mounting unit and moving up and down to come into contact with the socket and thereby provide a target temperature, and a temperature display displaying the target temperature,

wherein the chamber comprises:

a block inserted into the socket;

a thermoelectric element seated on an upper portion of the block;

a water jacket seated on an upper portion of the thermoelectric element and circulating cooling water therein; and

a cooling fan provided in the water jacket to blow air downwards, with a discharge hole being formed on a lower surface of the block to discharge nitrogen gas.

2. The hot/cold test equipment as set forth in claim 1, wherein the block is elastically supported in the chamber.

3. The hot/cold test equipment as set forth in claim 2, wherein the socket comprises an adapter into which a lower end of the block is inserted, with pinholes being formed in a bottom of the adapter to cause pins making contact with the memory to protrude towards the block when the block is pressed against the adapter.

4. The hot/cold test equipment as set forth in claim 1, further comprising:

a nitrogen generator provided under the mounting unit to supply the nitrogen gas to the discharge hole.

5. The hot/cold test equipment as set forth in claim 1, wherein the block comprises an upper block that comes into contact with a lower portion of the thermoelectric element, and a lower block that is coupled to a lower portion of the upper block and is inserted into the socket, and the heat pipe is provided between the upper block and the lower block, and a temperature sensor is provided in an interior adjacent to a bottom of the lower block to be connected to the temperature display.

6. The hot/cold test equipment as set forth in claim 5, wherein outer portions of the block and the thermoelectric element are surrounded by an insulator.

7. The hot/cold test equipment as set forth in claim 5, wherein a wick made of copper is provided in the heat pipe in such a way as to extend from an evaporation portion to a middle portion of the heat pipe.

8. Hot/cold test equipment for a Nand Flash Memory, comprising a mounting unit that contains the Nand Flash Memory together with a socket to test whether the memory is defective or not, a chamber provided above the mounting unit and moving up and down to come into contact with the socket and thereby provide a target temperature, and a temperature display displaying the target temperature,

wherein the chamber comprises:

a block inserted into the socket;

a thermoelectric element seated on an upper portion of the block;

a heat pipe seated on an upper portion of the thermoelectric element;

a radiator seated on an upper portion of the heat pipe; and

a radiation fan disposed above the radiator to blow air downwards.

9. The hot/cold test equipment as set forth in claim 8, wherein the block is elastically supported in the chamber.

10. The hot/cold test equipment as set forth in claim 9, wherein the socket comprises an adapter into which a lower end of the block is inserted, with pinholes being formed in a bottom of the adapter to cause pins making contact with the memory to protrude towards the block when the block is pressed against the adapter.

11. The hot/cold test equipment as set forth in claim 8, wherein the block comprises an upper block that comes into contact with a lower portion of the thermoelectric element, and a lower block that is coupled to a lower portion of the upper block and is inserted into the socket, and the heat pipe is provided between the upper block and the lower block, and a temperature sensor is provided in an interior adjacent to a bottom of the lower block to be connected to the temperature display.

12. The hot/cold test equipment as set forth in claim 11, wherein outer portions of the block and the thermoelectric element are surrounded by an insulator.

13. The hot/cold test equipment as set forth in claim 11, wherein a wick made of copper is provided in the heat pipe in such a way as to extend from an evaporation portion to a middle portion of the heat pipe.