CN101179040A - Method for identifying whether main reference plane position of silicon chip is correct or not - Google Patents

Abstract

The invention provides a method for identifying whether the location of the main reference surface of a silicon wafer is right, with the following steps: (1) electrifying and preheating an X ray diffractometer; loosing a knob, displacing a detector to 26 DEG 40 MIN and locking the knob; configuring an angle presetting switch to 13 DEG 20 MIN, turning on a vacuum pump switch, putting a sample on a testing table, opening an X ray slot switch, and turning the sample to 13 DEG 20 MIN by hand-wheel; and fine turning the hand-wheel to maximize the indication of the pointer of an mA meter and pressing a reset button. And (2) loosing the knob, displacing the detector to 88 DEG and locking the knob; sticking the main reference surface upwards to a bracket, opening the X ray slot switch, and turning the hand-wheel till the pointer of the mA meter indicates the maximum. If the angle is in the range of 24 DEG 32 MIN plus or minus 7.5 DEG, the location of the main reference surface is right; and if the mA meter has no response or the angle surpasses the range of 24 DEG 32 MIN plus or minus 7.5 DEG, the location of the main reference surface is improper. The method for identifying whether the location of the main reference surface of the silicon wafer is right is simple and feasible with high accuracy.

Description

Differentiate whether correct method of main reference plane position of silicon chip

[technical field]

The invention belongs to the silicon chip processing technique field, especially relate to whether correct method of a kind of discriminating main reference plane position of silicon chip.

[background technology]

In the silicon chip processing and device production process of microelectronic, the plane of reference plays the effect of identification and location, and it is the datum level that silicon chip is divided chip, and therefore, the plane of reference is one of standardized important content of silicon chip.We know, device production at first is will produce several to separate tube core or circuit on silicon chip surface, the mode that adopts scribing to cut apart then is divided into separate unit to tube core or circuit, again these separate units is loaded onto support, presses lead-in wire, is encapsulated in the shell and makes device.Because silicon crystal has anisotropic characteristics, so should select best scribing dividing method during scribing, otherwise will cause die yield to reduce.One of principle that the plane of reference is selected is corresponding to the cleavage surface of crystal.The crystal preparation in (111) used always and (100) crystal orientation is determined according to above-mentioned principle.In the prior art, usually the scribing of square or rectangle tube core being cut apart is that plane of reference direction by silicon chip preparation is in advance carried out.The problem that exists is: conventional process flow is by range estimation monocrystalline main ridge, find out several main ribs of monocrystalline, according to the difference in the crystal orientation monocrystalline main reference plane position that draws,, will cause the making mistake of the monocrystal rod plane of reference again in case main rib is differentiated the identification error end to end that deviation or silicon single crystal bar occur.In the case, people are seeking always and after monocrystal rod is cut into silicon chip the main reference plane that draws are being carried out the means that correctness is judged, and means that in fact also never find so far and method detect and judge whether the main reference plane of monocrystal rod is correct, to avoid continuing to occur mistake in the silicon chip following process, cause unnecessary loss.

[summary of the invention]

Whether be to solve the above-mentioned technical problem that prior art exists, the present invention aims to provide whether correct method of a kind of discriminating main reference plane position of silicon chip, correctly simple with this method judgement main reference plane position of silicon chip, accuracy rate is high.

Whether a kind of discriminating main reference plane position of silicon chip correct method, may further comprise the steps:

(1) instrument calibration: with x-ray instrument energising back preheating 15 minutes; Unclamp the fastening hand of detector carriage and turn round, detector is moved to 26 ° of 40 ' positions, the locking hand is turned round; Again the angle initialize switch is placed 13 ° 20 ', connect vacuum pump switch, standard proof print is posted testing stand, draw back x-ray slit switch, rotate the angular instrument handwheel, make standard proof print turn to 13 ° 20 ': rotate the angular instrument handwheel slightly, maximum up to mA list index indication, press reset strong.

(2) judge

Unclamp the fastening hand of detector carriage and turn round, detector is moved to 88 ° position, the locking hand is turned round; Then, be close to the main reference plane of tested silicon chip on the support up, draw back the x-ray switch, rotate the angular instrument handwheel, maximum up to the indication of mA table, be presented in 24 ° 32 ' ± 7.5 ° scopes as angle value, can judge that then main reference plane position is correct, not having reaction or angle value to show as the mA table exceeds 24 ° 32 ' ± 7.5 ° scopes, judges that then main reference plane position is incorrect.

Whether aforesaid a kind of discriminating main reference plane position of silicon chip correct method, it is characterized in that: be presented in 24 ° 32 ' ± 7.5 ° scopes as angle value, then can determine that fully main reference plane position is correct.

Beneficial effect: the applicant adopts the x-ray instrument, has drawn the angular range value of judging that main reference plane position of silicon chip is whether correct through repetition test, thereby has judged accurately whether reference plane position is correct, and its accuracy rate can reach 100%.

[embodiment]

The present invention confirms the correctness of main reference plane position of silicon chip by utilizing the X-ray direction finder.

As:＜111〉silicon chip＜211〉face incidence angle θ is 44 °, utilizes the interplanar angle relation of cubic crystal, can draw:

Main reference plane position angle=θ angle-{ angles between (211) and (111) }

＝44°-19°28′＝24°32′

That is: the detector of X-ray direction finder is placed on ° position, 2 θ angle=88, main reference plane rotates the angular instrument handwheel up, up to the swing of mA table maximum (24 ° 32 ' near), then this main reference plane position is correct.If 24 ° 32 ' near mA table do not show this main reference plane position mistake then.

Step is as follows:

(1) instrument calibration: with x-ray instrument energising back preheating 15 minutes; Unclamp the fastening hand of detector carriage and turn round, detector is moved to 26 ° of 40 ' positions, the locking hand is turned round; Again the angle initialize switch is placed 13 ° 20 ', connect vacuum pump switch, standard proof print is posted testing stand, draw back x-ray slit switch, rotate the angular instrument handwheel, make standard proof print turn to 13 ° 20 '; Slightly rotate the angular instrument handwheel, maximum up to the indication of mA list index, press reset strong;

(2) judge

Unclamp the fastening hand of detector carriage and turn round, detector is moved to 88 ° position, the locking hand is turned round; Then, be close to the main reference plane of tested silicon chip on the support up, draw back the x-ray switch, rotate the angular instrument handwheel, maximum up to the indication of mA table, be presented in 24 ° 32 ' ± 7.5 ° scopes as angle value, can judge that then main reference plane position is correct, not having reaction or angle value to show as the mA table exceeds 24 ° 32 ' ± 7.5 ° scopes, judges that then main reference plane position is incorrect.

Whether aforesaid a kind of discriminating main reference plane position of silicon chip correct method, it is characterized in that: maximum as the indication of mA table, its angle value is presented in 24 ° 32 ' ± 7.5 ° scopes, then can determine that fully main reference plane position is correct.

Adopted YX-O2D type X-ray direction finder in following examples.

Embodiment one:

After instrument calibration finishes, be close to 4 inches＜111〉main reference plane position of silicon chip up on the support, draw back the X ray switch, rotate the angular instrument handwheel, maximum up to mA table indication, the reading on this moment display be 24 ° 40 ', can judge that this main reference plane position of silicon chip is correct.

Embodiment two:

After instrument calibration finishes, be close to 5 inches＜111〉main reference plane position of silicon chip up on the support, draw back the X ray switch, rotate the angular instrument handwheel, maximum up to mA table indication, the reading on this moment display be 24 ° 28 ', can judge that this main reference plane position of silicon chip is correct.

Embodiment three:

After instrument calibration finishes, be close to 6 inches＜111〉main reference plane position of silicon chip up on the support, draw back the X ray switch, rotate the angular instrument handwheel, maximum up to mA table indication, the reading on this moment display be 24 ° 30 ', can judge that this main reference plane position of silicon chip is correct.

Claims (2)

1. differentiate whether correct method of main reference plane position of silicon chip for one kind, may further comprise the steps:

(1) instrument calibration: with x-ray instrument energising back preheating 15 minutes; Unclamp the fastening hand of detector carriage and turn round, detector is moved to 26 ° of 40 ' positions, the locking hand is turned round; Again the angle initialize switch is placed 13 ° 20 ', connect vacuum pump switch, standard proof print is posted testing stand, draw back x-ray slit switch, rotate the angular instrument handwheel, make standard proof print turn to 13 ° 20 '; Slightly rotate the angular instrument handwheel, maximum up to the indication of mA list index, press reset strong;

(2) judge

Unclamp the fastening hand of detector carriage and turn round, detector is moved to 88 ° position, the locking hand is turned round; Then, be close to the main reference plane of tested silicon chip on the support up, draw back the x-ray switch, rotate the angular instrument handwheel, maximum up to the indication of mA table, be presented in 24 ° 32 ' ± 7.5 ° scopes as angle value, can judge that then main reference plane position is correct, not having reaction or angle value to show as the mA table exceeds 24 ° 32 ' ± 7.5 ° scopes, judges that then main reference plane position is incorrect.

2. whether a kind of discriminating main reference plane position of silicon chip as claimed in claim 1 correct method, it is characterized in that: be presented in 24 ° 32 ' ± 7.5 ° scopes as angle value, can determine that then main reference plane position is correct.