The self-operated measuring unit in serviceable life of cmp head spacing ring
Technical field
The utility model relates to a kind of pick-up unit, relates in particular to a kind of measurement mechanism of cmp head spacing ring.
Background technology
CMP is meant cmp (Chemical Mechanical Polishing), or is called chemical-mechanical planarization (Chemical Mechanical Planarization).Chemical mechanical milling tech is the technological process of a complexity, it is that crystal column surface is contacted with the lapped face of grinding pad, then, by the relative motion between crystal column surface and the lapped face with flattening wafer surface, the common chemical-mechanical grinding device that adopts is also referred to as grinder station or polishing machine platform carries out chemical mechanical milling tech.Described grinder station comprises a cmp head, when carrying out grinding technics, the wafer that will grind is attached on the grinding head, this wafer to be ground faces down and contacts counterrotating grinding pad, the downforce that grinding head provides is pressed onto this wafer on the grinding pad, described grinding pad is to be pasted on the platform, and when rotating under the drive of this platform at motor, grinding head also carries out relative motion; Simultaneously, lapping liquid is transported on the grinding pad by the lapping liquid supply line, and is evenly distributed on the grinding pad by centrifugal force.The employed lapping liquid of grinding technics generally includes chemical mordant and abrasive grains, chemical reaction by chemical mordant and described surface to be ground generates softer easy to be removed material, remove from the surface of being ground wafer by the mechanical friction material that these are softer then, reach the effect of overall planarization.
Specifically see also Fig. 1, it is the user mode synoptic diagram of cmp head.After injecting lapping liquid on the grinding pad 6 of grinder station, by (membrane) 8 of the film in the grinding head 4 wafer 7 is pressed on the grinding pad 6 and grinds.The purpose of grinding is that dielectric layer on the wafer 7 (oxide layer) and metal level (metal layer) are polished, make its global planarization and then carry out solid wiring or multilayer wiring, promote distribution density (pattern density), reduce defect concentration (defect density) simultaneously, promote process rate.At present, utilizing the CMP of nanometer technology is the method for the most effective realization flattening wafer surface.
Please continue to consult Fig. 1, described cmp head 4 also comprises an annular element that is used to limit the regional activity that wafer 7 controlled at cmp head 4, it is spacing ring 5, be also referred to as retaining ring, described spacing ring 5 is circular endless loop, the internal diameter of described spacing ring 5 cooperates the external diameter of wafer, positions in order to the neighboring of fit wafer, skids off outside the spacing ring 5 to prevent wafer; When grinding, the lower surface of described spacing ring 5 can contact with grinding pad 6.See also Fig. 2, it is the elevational schematic view of described spacing ring.As seen from Figure 2, be laid with several grooves 51 around the lower surface of described spacing ring 5, described groove 51 runs through the width of spacing ring 5, described groove 51 is in order to when grinding wafer rotates, the centrifugal force that utilizes rotation to produce throws away the discarded object that grinding produces, and helps lapping liquid through described groove 51 inflows and outflow.
Yet, since spacing ring in process of lapping can and grinding pad contact and mutual friction mutually, thereby spacing ring can produce wearing and tearing, and arranged certain serviceable life.For the serviceable life of spacing ring, we can be at different processing procedures, being set in 4000 the serviceable life of spacing ring in 7000 wafer scopes usually.At present, mainly adopt the mode of manual record, write down the use sheet number (promptly using the quantity of the wafer of this spacing ring grinding) of spacing ring.But the phenomenon of manual record error takes place through regular meeting, if current residual much smaller than actual probable life serviceable life, is changed in advance and scrapped this spacing ring, caused waste, this error also is not easy in time to be found, also can't accurately reduces its current real serviceable life even be found; If current residual can cause the spacing ring excessive wear much larger than actual probable life serviceable life, cause product serious defective to occur, even cause slide plate and fragmentation, and this error also is not easy in time to be found; In addition, spacing ring of the same race is its degree of wear and inconsistent after using extremely identical sheet number, because its degree of wear also needs to depend on the various conditions in the use, and as pressure, temperature, factors such as lapping liquid flow size.
In sum, only to limit the serviceable life of spacing ring be very unilateral and complex operation to the sheet number of the wafer that grinds with spacing ring, makes mistakes easily.In case the historical wafer of this spacing ring uses the record of sheet number to lose, the remaining life of this spacing ring just is in no position to take possession of.Therefore, how providing a kind of self-operated measuring unit in serviceable life of cmp head spacing ring is the technical matters that those skilled in the art need to be resolved hurrily.
The utility model content
The purpose of this utility model is to provide a kind of self-operated measuring unit in serviceable life of cmp head spacing ring, by the gash depth that records and utilize gash depth and the proportional relationship in the serviceable life of spacing ring can calculate the remaining life of spacing ring.
To achieve the above object, the utility model adopts following technical scheme:
A kind of self-operated measuring unit in serviceable life of cmp head spacing ring, be laid with some grooves on the described spacing ring, described self-operated measuring unit comprises control device and is used to detect the pick-up unit of described gash depth that described pick-up unit is connected with described control device.
Preferably, described pick-up unit is the depth detection instrument.
Preferably, described depth detection instrument is a linear displacement transducer, and described linear displacement transducer comprises the variable resistor slide rail and have the slide block of thimble that described slide block moves relative to described variable resistor slide rail.
Preferably, described depth detection instrument comprises a variable resistor guide rod, push rod, horizon bar, first spring and second spring, described variable resistor guide rod and push rod are arranged with first spring and second spring respectively, the same side of described first spring and second spring is fixedlyed connected with described horizon bar respectively, and described horizon bar is provided with a contact that contacts with the variable resistor guide rod all the time.
Preferably, described pick-up unit comprises two depth detection instruments, and described two depth detection instruments lay respectively at two relative grooves on the described spacing ring.
Preferably, described automatic detection device also comprises warning device, and described warning device links to each other with described control device.
The beneficial effects of the utility model are as follows:
The self-operated measuring unit in serviceable life of the utility model cmp head spacing ring, measure the degree of depth of groove and this depth information is transferred to control device by pick-up unit, described control device can and be stored in the gash depth of spacing ring of control device inside and the corresponding relation of the remaining life of spacing ring compares in advance with this depth information, thereby obtains the remaining life of this spacing ring automatically.The self-operated measuring unit in serviceable life of the utility model cmp head spacing ring uses the method for remaining life of the acquisition spacing ring of sheet number with respect to original wafer by artificial record spacing ring, automaticity height not only, avoided the human operational error, and need not to utilize the wafer of spacing ring to use sheet to count historical record, just can calculate the remaining life of all spacing rings.
Description of drawings
The self-operated measuring unit in serviceable life of cmp head spacing ring of the present utility model is provided by following embodiment and accompanying drawing.
Fig. 1 is the user mode synoptic diagram of cmp head;
Fig. 2 is the elevational schematic view of spacing ring;
Fig. 3 is the principle schematic of embodiment 1 of the present utility model;
Fig. 4 is the depth detection instrument structural representation of embodiment 1 of the present utility model;
Fig. 5 is the user mode synoptic diagram of embodiment 1 of the present utility model;
Fig. 6 is the depth detection instrument structural representation of embodiment 2 of the present utility model;
Fig. 7 is the user mode synoptic diagram of embodiment 2 of the present utility model.
Among the figure, 1-pick-up unit, 11-variable resistor slide rail, 111-top, 112-end, 12-slide block, 13-thimble, 2-control device, 3-warning device, 4-grinding head, 5-spacing ring, 51-groove, 6-grinding pad, 7-wafer, 8-film, 91-variable resistor guide rod, 92-push rod, 93-horizon bar, 94-first spring, 95-second spring, 96-contact.
Embodiment
Below will the self-operated measuring unit in serviceable life of cmp head spacing ring of the present utility model be described in further detail.
Below with reference to accompanying drawings the utility model is described in more detail, has wherein represented preferred embodiment of the present utility model, should be appreciated that those skilled in the art can revise the utility model described here and still realize advantageous effects of the present utility model.Therefore, following description is appreciated that extensively knowing for those skilled in the art, and not as to restriction of the present utility model.
For clear, whole features of practical embodiments are not described.In the following description, be not described in detail known function and structure, because they can make the utility model because unnecessary details and confusion.Will be understood that in the exploitation of any practical embodiments, must make a large amount of implementation details, for example, change into another embodiment by an embodiment according to relevant system or relevant commercial restriction to realize developer's specific objective.In addition, will be understood that this development may be complicated and time-consuming, but only be routine work to those skilled in the art.
For the purpose of this utility model, feature are become apparent, embodiment of the present utility model is further described below in conjunction with accompanying drawing.It should be noted that accompanying drawing all adopts very the form of simplifying and all uses non-ratio accurately, only in order to convenient, the purpose of aid illustration the utility model embodiment lucidly.
Embodiment 1
See also Fig. 3-Fig. 5, wherein, Fig. 3 is the principle schematic of embodiment 1 of the present utility model; Fig. 4 is the depth detection instrument structural representation of embodiment 1 of the present utility model; Fig. 5 is the user mode synoptic diagram of embodiment 1 of the present utility model.
The self-operated measuring unit in serviceable life of this cmp head spacing ring is used to calculate the remaining life of spacing ring 5.Lay some grooves 51 on the described spacing ring 5.Described gash depth self-operated measuring unit comprises control device 2 and is used to detect the pick-up unit 1 of described gash depth, described pick-up unit 1 is connected with described control device 2, and described control device 2 receives and analyze the gash depth information from described pick-up unit 1.Owing to learn through scientific research personnel's repetition test, become certain proportional relationship with gash depth on the spacing ring serviceable life of spacing ring, that is, gash depth is shallow more, and the serviceable life of spacing ring is short more.Therefore, during use, at first utilize described pick-up unit 1 to measure the degree of depth of groove 51, then this depth information is transferred to control device 2, described control device 2 is with this depth information and be stored in the gash depth of spacing ring 5 of control device 2 inside in advance and the corresponding relation of the remaining life of spacing ring 5 compares, thereby just obtains the remaining life of this spacing ring 5 automatically.
In the present embodiment, described pick-up unit 1 is a kind of depth detection instrument, promptly as long as be transferred in the control device 2 after this depth detection instrument can convert depth information to electric signal.The kind of described depth detection instrument is more, is that example describes with the linear displacement transducer at this.
The concrete structure of described linear displacement transducer comprises variable resistor slide rail 11 and has the slide block of thimble 13 that described slide block moves relative to described variable resistor slide rail 11.The function of described linear displacement transducer is that a straight line mechanical displacement converts electric signal to.Described variable resistor slide rail 11 comprises top 111 and terminal 112, during measurement, described terminal 112 withstand on the lower surface of described spacing ring 5, connect the stable state DC voltage between the top 111 of variable resistor slide rail 11 and terminal 112, allow to flow through the little electric current of micromicroampere, the voltage between described slide block and the top 111 is directly proportional with the length that slide block 12 moves.Linear displacement transducer sends to control device 2 with the voltage signal between described slide block 12 and the top 111.Described control device 2 converts this voltage signal to depth information, and the corresponding relation of the remaining life of the gash depth of this depth information and the spacing ring 5 that is stored in control device 2 inside in advance and spacing ring 5 compared, thereby obtain the remaining life of this spacing ring 5 automatically.
Preferably, described pick-up unit 1 comprises two depth detection instruments, two relative grooves 51 on the described cmp head of described two the depth detection instruments difference displacement spacing ring 5.These two depth detection instruments send to control device 2 respectively with the voltage signal that records, and control device 2 calculates the remaining life of spacing ring 5 according to the mean value of two voltage signals.
Preferably, described serviceable life, automatic detection device 1 also comprised warning device 3, and described warning device 3 links to each other with control device 2.When the remaining life of spacing ring 5 during less than predefined warning value, report to the police by warning device 3, so that operating personnel in time change spacing ring 5, guarantee to grind that processing procedure is stable smoothly carries out.
Embodiment 2
See also Fig. 6 and Fig. 7, wherein, Fig. 6 is the depth detection instrument structural representation of embodiment 2 of the present utility model; Fig. 7 is the user mode synoptic diagram of embodiment 2 of the present utility model.
The difference of present embodiment and embodiment 1 is:
Described depth detection instrument comprises a variable resistor guide rod 91, push rod 92, horizon bar 93 and two springs (i.e. first spring 94 and second spring 95), described variable resistor guide rod 91 and push rod 82 are arranged with first spring 94 and second spring 95 respectively, the same side of described first spring 94 and second spring 95 is fixedlyed connected with described horizon bar 93 respectively, and described horizon bar 93 is provided with a contact 96 that contacts with variable resistor guide rod 91 all the time.During use, between the two ends of variable resistor guide rod 91, connect the stable state DC voltage in advance, allow to flow through the little electric current of micromicroampere.Then, horizon bar 93 is close to 5 lower surface of described spacing ring.Then, the lower ends downward of variable resistor guide rod 91 is moved on the bottom surface of pushing up described groove 51, this moment contact 96 all the time with described variable resistor guide rod 91 sliding contacts.Voltage between described contact 96 and variable resistor guide rod 91 lower ends is directly proportional with distance between described contact 96 and variable resistor guide rod 91 lower ends.At last, described depth detection instrument sends to control device with variable resistor guide rod 91 with the voltage signal between described contact 96 and variable resistor guide rod 91 lower ends.
In sum, the self-operated measuring unit in serviceable life of the utility model cmp head spacing ring, measure the degree of depth of groove and this depth information is transferred to control device by pick-up unit, described control device can and be stored in the gash depth of spacing ring of control device inside and the corresponding relation of the remaining life of spacing ring compares in advance with this depth information, thereby obtains the remaining life of this spacing ring automatically.The self-operated measuring unit in serviceable life of the utility model cmp head spacing ring, with respect to original artificially method of the remaining life of the acquisition spacing ring of the wafer use sheet number of record spacing ring of passing through, automaticity height not only, avoided the human operational error, and need not to utilize the wafer of spacing ring to use sheet to count historical record, just can calculate the remaining life of all spacing rings.
Obviously, those skilled in the art can carry out various changes and modification to the utility model and not break away from spirit and scope of the present utility model.Like this, if of the present utility model these are revised and modification belongs within the scope of the utility model claim and equivalent technologies thereof, then the utility model also is intended to comprise these changes and modification interior.