вход по аккаунту



код для вставкиСкачать
Patent Translate
Powered by EPO and Google
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
t Title of invention
Semiconductor pressure sensitive device and its manufacturing method
Detailed Description of the Invention The present invention deposits a tin oxide film on a
semiconductor substrate to form a rectifying barrier K. An insulating film having a thickness of
20 to 5 ojl between the substrate and the tin oxide film. The present invention relates to a
semiconductor pressure sensitive device in which Conventionally, the pressure using a
semiconductor element is also mainly an electrical quantity conversion element utilizing a PI +
junction, and such a pressure sensitive element must apply pressure in the vicinity of a planar
type PN junction extending over the entire surface of the semiconductor substrate. It is difficult
to set the position of the presser, and it is a disadvantage that diffusion treatment at high
temperature is required to form PN housing, and furthermore, the pressure-sensitive
characteristics are not preferable because they exhibit square characteristics. The The so-called
Schottky barrier between semiconductor and metal is also known to exhibit pressure-sensitive
properties, or it is difficult to set the deposition conditions of the metal, and the pressure changes
the properties of the metal due to deformation of the metal. There is a drawback of EndPage: 1.
In recent years, as a pressure-sensitive element for solving such a defect, as shown in FIG. 6, a
rectifying barrier 63 'is formed by the semiconductor base & 61 and the tin oxide film 62, and
pressing means 64 for the barrier region is used. It has already been devised whether it was
established. In order to manufacture the device having the above-mentioned structure, the
inventors use a semiconductor single crystal plate as a semiconductor substrate 61, for example,
and generate # silver film (SnQ film 62 by thermal decomposition reaction on this silicon single
crystal plate). As a result, there are some drawbacks in that the variation of reverse breakdown
voltage in the pressure-sensitive element of this S51-8 nOs combined structure is large and
leakage and leakage in the reverse direction are large, and the breakdown is not necessarily
sufficient. I had it. Therefore, as a result of the inventor group's deep consideration from all
points of view, an aiot cover II (not shown) is formed between the silicon substrate 61 and the tin
oxide (3n02) film 62, and this 810! It is easy to see that the surface of the silicon substrate 610
is easily oxidized (, “c'hb”, “Open-sho 48-96088 (2)” in general, in view of the fact that the
coating is giving the influence of a doghouse. As a result of the film being formed on the surface
of this substrate even in the natural environment prior to the formation of the Sn0w film and also
during the film formation step of S / IO, this SiO. It is easily understood that it is of the nature
that is necessarily interposed between the 61 and the Snow film 62. In order to examine the
influence of this 910 * coating in detail Kf14, the inventors first removed the 5sot @ waist on the
silicon base N 61 and then formed the 5nOx film 62vt by a means such that the KSiOt film on
this substrate was not formed. A pressure sensitive element having a 5i-6 nQy structure in a socalled near pure sense as shown in FIG. 6 was manufactured.
Generally, as a means to remove the SiO * film on the seacon substrate and deposit 5 nOx,
whether the silicon substrate surface is polished with an electron beam in ultra-high vacuum and
then the SnO * is steamed (see FIG. 7) Then, there is a method of depositing% Bt% Qt of which the
substrate surface was cleaned with a diluted solution of HP (see s8 in FIG. 11). Therefore, the
present inventors have not, and a pressure-sensitive device of the fli-SnQw structure was
manufactured using the vacuum evaporation method as the first means. Now, this will be
described with reference to FIG. 7. After the inside of the vacuum chamber 71 is exhausted from
the exhaust lower 2 by the ion pump (not shown) to a vacuum state of 1 o -1, the electron beam
gun 73 is The surface of the silicon substrate 61 provided on the support base 74 is polished by
polishing with the surface it. Thereafter, the tin 75 provided on the% ster 74 is Kli-deposited on
the silicon base W 61 polished as described above, and exposed to an oxidizing atmosphere of
the outside air to oxidize only the deposited tin 62 '. Manufactured a pressure-sensitive element
as shown in Figure 136 9. Next, the inventors manufactured a t81-9 nOtll pressure sensor as
shown by the sixth FltJK using the second method, vapor phase growth method. That is, in the
inert gas chamber (not shown). With the dilution liquid of the following, wash the board
substrate 61 and set the board substrate 61 from which SiOx [film is removed] on the quartz
boat formation in the quartz tube 81 shown in the eighth WJ 1 by the heating heater 83 While
heating up to about sOD ° C., the cock 84 is opened to flow the inert gas X from the inflow port
85 and is discharged from the outflow port 86 in order to prevent oxidation of the silicon
substrate surface. The inert atmosphere Elf <. When the silicon substrate 61 is heated to about
500 ° C., the cock 84 is closed to shut off the inflow of the inert gas X, and at the same time, the
Kochta 87 is opened to use 8 nC1 of oxygen flowing from another inflow Hita. The heavy gas Y is
fed onto the above-mentioned seacon substrate 1 to deposit and generate the front and rear
Ksnot films 62 of the silicon substrate 61. In the devices manufactured by both the fk first and
second methods as described above, the rectifying insulator 64 formed between the silicon base
$ 61 and the Sn0w film 62. As shown in FIG. 6, there is no KSiOm film as shown in FIG. 6, and it
has been confirmed that even if 810 has the fact that the film is intervened, it has an extremely
thin film thickness of about several contributions. Then, the reverse bias power supply 67 is
connected between the electrode 65 shown in FIG. 4 and the image, the current value is read
with the current needle EndPage: 2, and the voltage / current slope of the element is drawn. As
shown by the characteristic curve (a) in FIG. 3 in the case of the vacuum deposition method of
one method, and as shown by the curve (2) in the same figure in the case of the vapor phase
growth method of the second method. Leakage current in reverse voltage-current characteristics
-5 = 11 = == 9 ===================================================== As shown by -f (in
the case of the second vapor phase growth method), it has a large variation.
Furthermore, it has been found that the leakage current at the film thickness of the S10 * film is
at or near 0, as described in detail later, is extremely high, and the withstand voltage decreases
accordingly. By the way, the curve i in FIG. As shown by fp ;, the large variation in reverse
breakdown voltage vb is caused at low pressure load if the pressure-sensitive accuracy as the
pressure-sensitive element is poor, the leakage current in the reverse direction is large. Current is
extremely small compared to leakage current, so that the so-called Sr1 ratio is a bad defect or the
device withstand voltage is low due to the detection or failure of the net pressure-sensitive
current. Given the large restriction on applied voltage at the time, it has M types of defects such
as very limited use. J-- 1 In the present invention, the usual means on the silicon substrate 61,
that is, S10! By trying to form the Sn0w coating 62 by means that does not take account of the
surface so as to actively suppress the formation of the coating, S10! A coating (not shown) is
produced, this 810! The film thickness of the stow @ film does not reach more than zoRNWt
from the various experimental data, and the influence of the film on the characteristics is
examined. The reverse breakdown voltage vb in that case, the reverse leakage current , S10!
Although a good trend could be found compared to the one without the inclusion of a coating, it
was still not satisfactory. By the way, as a reason for showing a tendency to slightly improve the
variation in reverse breakdown voltage vb, the leak current in the reverse direction, and the
breakdown voltage when the film thickness is as small as less than 20 contributions between the
silicon substrate and the Sn0w film. You can think of it as follows. That is, when there is no 5ift
film, this tin enters the crystal defect when the deposition or formation of tin occurs in the
rounding of the crystal defect of the silicon substrate, and the crystal defect is not uniform. The
variation in yb is considered to give rise to large results, and the 5 n Ot film is in contact with the
surface of the silicon substrate in a straight wall, so the withstand voltage is low, and the leakage
current in the reverse direction is accompanied thereby Is also considered to be large. Therefore,
when a number R to about 20 R Sil addictive film is interposed between the silicon substrate and
the 8n 04 film, the 810 sacrificial film or a defect on the silicon substrate is covered to suppress
the leak current in the reverse direction, and It also helps to improve the breakdown voltage, and
as the 810 snow cover acts like a suitable cover film to prevent tin from entering the crystal
defects of the silicon substrate, the variation in reverse breakdown voltage vb is small. It is
thought that it shows the tendency.
However, such poles (thin 810! In the film, the entire surface of the silicon substrate is not
completely covered, and the% SSO double film may be scattered in the form of islands on the
silicon substrate, or the film thickness may be uneven, and the covering state is Because of the
variety, it has been very difficult to obtain a uniform, uniform characteristic pressure sensitive
device, and the device production yield is low. And the above-mentioned thing is not limited to
the case where the semiconductor substrate is used as the semiconductor substrate, but P-type
silicon, sacred germanium, and sacred helium are used, and the nine insulating films are S10! It
has been confirmed that even if 811 m, 示 す 10 z, etc. are used instead of, the lj 3 -like tendency
is exhibited. Therefore, one object of the present invention is to use a substance which causes a
rectifying butchery on a semiconductor substrate (for example, to attach a layer, interposing an
insulating film on both of them), and setting the film thickness of this insulating film to a
predetermined value It is an object of the present invention to provide a semiconductor pressuresensitive device capable of reducing the reverse breakdown voltage vb / illumination and reverse
leakage current by selecting EndPage: 3 and improving the withstand voltage. Another object of
the present invention is to provide a semiconductor pressure sensitive device that can be
manufactured. Still another object of the present invention is to set the thickness of the thin film
of silicon oxide to a predetermined value, and after removing the borooxide film formed on the
surface of the substrate of the substrate, the new oxide film The present invention provides a
method of manufacturing a pressure-sensitive element capable of generating a predetermined
value to facilitate control of the film formation and improving the manufacturing yield. Next, to
further understand the present invention, the illustrated embodiment will be described. FIG. 1
shows an example of the semiconductor pressure sensitive device according to the present
invention, in which 1 is a wedge-shaped silicon substrate, 2 is an insulating film, 3 is a silver
halide coated III, 4 is an electrode metal, 5 is an electrode metal. A pressurizer, 6 is a bias DC
power supply, and 7 is a current needle. Type 1 silicon substrate 1 has a resistivity of 1 fl − (! A
silicon single crystal plate at the 1st position is used, which is an insulating film 24 or a silicon
oxide film (BiO), and the insulating film 2 is formed on the main surface of the substrate by
thermal oxidation of the silicon substrate 1 or the like. Also, even if another insulating film such
as KSiiNs film is used instead of 5iOt film, 1! After 2 is formed on the above-mentioned insulating
covering 1 which does not support, a tin oxide (Sr + Ot) film 5 is formed by the method described
in 1 ltc in detail. Form an eyebrow. When the pressure sensor 5 of the semiconductor pressurecollector configured as described above is pressed, the barrier between the silicon group @ 1 and
the tin oxide film 5 is changed, and the flowability is changed accordingly.
Next, the process of forming the tin oxide film S in the process of manufacturing the
semiconductor pressure-sensitive element of the one upper arrangement will be described in
detail with reference to the manufacturing apparatus shown in FIG. In FIG. 2, 11 is an oxidizing
gas nose, for example, an oxidizing gas feed pipe for feeding oxygen or air or a mixture of oxygen
and nitrogen, and 11 'is for feeding an inert gas a', for example, nitrogen gas. 13. inert gas inlet
pipe, 12, 12 'is a gas flow meter, 13. I5 'is a valve for controlling the flow rate of the above gas a,
a ′ ′, 14 is a liquid containing dimethyldichloride ((cm · tF3nC1t ′ ′) sealed and a 9
evaporator, and 15 is a vapor C of dimethyl dichloride silver and air a ′ And a valve for
controlling the flow rate Q of the mixture 6. 17 is an evaporator in which water O is enclosed, 18
is a water vapor feeding pipe, and a steam inlet pipe 19; 19 is an oil reservoir containing an oil b
for heating the evaporators 14 and 17 to 110 ° C. to 150 ° C. is there. 21 is a quartz tube, 22
is a heater for heating the reaction part to 400 ° C. to 600 ° C. 23 is a boat of quartz or the
like. Single crystal plate 1 is placed. 25 is the mixture d #, and the quartz tube 21 receives the
steam f if necessary! , 26 is an exhaust end cap, 27 is an exhaust g exhaust port, 29.29 '' right
and 30 is a patch 1 island, and the exposed main surface is formed into a mirror surface or rough
surface by physical or chemical means in advance The cleaned MW Si substrate 1 is washed with
a dilution solution of FfF, and 610! Covered! I!! After being removed, and placed on a hortra
and inserted into the quartz tube 21. Then, the silicon substrate 1 is aged by the heater 22 to a
temperature of 400 ° C. to 600 ° C., preferably 500 ° C. When the silicon substrate 1 reaches
a predetermined temperature, the valve 13 and the cock 29jO are opened, and the oxidizing gas
a and the water vapor f are fed from the inlet tube 11.18, and the main surface tube of the silicon
substrate 1 is It is left in an oxidizing atmosphere for 2 minutes to 100 minutes, and 5101
targets 2 of 20R to soR are formed on this silicon substrate 1 as shown in FIG. The thickness of
this pan 0 membrane can be appropriately selected within the range of not less than 20% and
not more than soi. Also, the formation of relatively thick films such as 50 R or more raises the
temperature, for example (thermal oxidation in the furnace provided at 17 r 30 ° C., EndPage
during oxidation: 41% 11 (k It is also possible to adopt a method of shortening the
After the formation of the 31Q1 film 2, 1 <lube 13 'and the cock 29' are sent to Kangna and inert
carrier gas a 'is fed into the evaporator 14 of dimethyl silver halide through the feeding pipe 11'.
By the way, when this inert gas a 'passes through the inside of the oil chair 19, it is prepared to
some extent. Before, the oil path 19 is heated by a heater (not shown), and the oil h in the path
19 is heated to a specific temperature and a darkness at a temperature of 11 fl ′ ′ CJ to 15
Q′CK, for example 135 ° C. Dimethyltindichloride sealed in the crucible 1 is heated to a
constant temperature by an oil pass to generate a vapor O. In order to properly adjust the
conductivity of tin oxide test 5, a predetermined amount of antimony trichloride or another
antimony compound may be added to this dimethyldichloride to properly adjust the conductivity
of tin oxide test 5. The vapor of dimethyltin dichloride 1 filled in the evaporator 14 is carried by
passing of the carrier gas 畠 ′ ′, is evacuated under reduced pressure in an empty pump (not
shown), and is introduced into the quartz tube 21 b. 9. At the time of the introduction of the
mixture d, the steam f is also simultaneously introduced if necessary, and is mixed and added to
the mixture d. The dimethyl-tin chloride fed into the black-quartz tube 21 is thermally
decomposed to form a tin oxide film 3 on the 810 m film 2 as shown in FIG. It is presumed that
this decomposition formation is performed mainly by the reaction which is covered by the
following chemical reaction formula. That is, when the voltage '-current characteristics of the
pressure sensitive element of the junction are drawn, as shown by the curve (to) in FIG. 3, the
leakage current C is compared with the element (characteristic curve 1pl) of the 8l-8 nO *
junction. It was possible to obtain very few things. First, as indicated by the curve i of the fourth
meter, it was possible to obtain even less amount of reverse breakdown voltage of the abovementioned element in comparison with the characteristic curve-one. Further, when the
relationship between the leakage current in the reverse direction and the withstand voltage with
respect to the film thickness of the 810 g film 2 is regulated, the leakage current in the reverse
direction is increased as the film thickness 2 increases as shown in FIG. 80R's! I! Suddenly
decreases in thickness, and leakage current gradually approaches zero when the film thickness is
80R or more. On the other hand, it was found that the withstand voltage jumped in the range of
20 to 80 R with the increase of the film thickness of the I5 rtcssot film · 2 shown in Fig. 5 (C +
shown), and showed a cylindrical column completely opposite to the leakage current. . This is
believed to be the result of increasing the properties as an insulating coating as the thickness of
the 5 ift coating 2 or III increases. However, when the thickness of the piot film 2 is increased,
the rectifying characteristics are lowered and the sensitivity tends to be lowered by one degree.
Therefore, it is recommended to select the film thickness to 100% or less, preferably considering
the production process. Furthermore, the pressure-sensitive current characteristic diagram
shown in FIG. 5 (AJ and the ratio of the pressure-sensitive current I under pressure to the reverse
leakage current 1 under normal pressure shown in FIG. From the / i ratio characteristic diagram,
the above 810! It is further recommended to select the film thickness of the double film 2 to be
practically 20-- or preferably 20 to 6 offi. By the way, in the above embodiment, an insulating
film such as a film tc 810 on the silicon substrate 1 shown in FIG. In order to form the old
insulating film, the old insulating film is completely removed with a cleaning solution of Hv in a
state close to mt. The reason for newly forming the insulating coating 2 by lI is to make it easy to
control the thickness of the layer wi2. That is, some of them have a considerable time lapse from
the production of the general Kv1 con substrate 1 to the production of the pressure-sensitive
element shown in FIG. 1 and some of them do not. As described above, when the production time
of the silicon substrate 1 is large (if different ones are placed in the mass production process,
since the natural oxidation is generated on the shidakkon substrate 1, the film thickness is
uneven or not as old as 110 g. Under the non-uniform insulating film, a new insulating film is
laminated, and as a result, the film EndPage: 5 thickness of the insulating film 2 of the pressuresensitive element shown in FIG. Variations in the reverse bias voltage, leakage current, current,
and withstand voltage of the pressure sensitive device are IIE, and a device having desired
characteristics tends to be rounded, and the yield of device manufacture tends to deteriorate. It is
to improve. However, the old insulation film on the silicon substrate 1 does not necessarily need
to be removed, and the silicon substrate 1 may show much fluctuation at the time of
manufacture, and a uniform one of the old insulation film can be used, or The oxidation time of
the silicon substrate 1 with the oxidizing gas aK and the silicon group I! In the apparatus of FIG.
By appropriately controlling the oxidation temperature of i1, it becomes possible to control the
film thickness of the insulating film 2 constant and easily obtain nine elements having the
desired characteristics. The rectifying barrier in this type of pressure-sensitive element exhibits
photosensitive characteristics, and the pressure-sensitive characteristics change upon light
irradiation, so% jll [! It is desirable that the opaque nickel electrode 4 of 1 be extended over the
entire surface of Sr + Ot 1Is to be shielded by any amniotic membrane b. The silicon substrate 1
had a 2ss square, a thickness of 200 μ%, and a tin oxide 11B of 1 square inch, a thickness of 0.6
μ, and an R-type silicon substrate 10 having a specific resistance of 1 Ω-country.
The applied voltage was 50 mA. As described above in detail, according to the first invention, the
present invention provides an insulating film having a thickness of 20 to 80 R, such as filltc 810,
a film for forming a rectifying barrier and a semiconductor substrate and a material such as a
BaO2 film. Artificially and positively, so that the insulating film functions to reduce variation in
reverse breakdown voltage vb and leakage current, and to provide a semiconductor pressuresensitive device capable of improving withstand voltage. It is Next, according to the second
aspect of the present invention, 20-80 j between the silicon substrate and the Snug cover! By
interposing an 8101 @ film having a film thickness of, it is possible to provide a semiconductor
pressure sensitive device easy to manufacture. Furthermore, according to the third aspect of the
present invention, generally, an 810 m film has already been formed on a silicon substrate, so
after removing it, the film is newly formed 5io 4111! By taking the method of generating, 's! iけ
るS10! The formation accuracy of the film thickness of the film is improved and improved,
and the old non-uniformness becomes worse. ((1) Compared with the case where the valve R, inx
film is newly laminated on the film, the film thickness is uniform It has the excellent advantages
of line types, such as being able to ensure quality and uniformity and quality, and being able to
obtain better 1 * performance results and improved device manufacturing yield.
4. Brief description of the drawings FIG. 1 is a longitudinal sectional view showing an example of
a semiconductor pressure-sensitive device according to the present invention, and FIG. 2 is a
system diagram showing an example of a pressure-sensitive device manufacturing apparatus
shown in FIG. Figures 3 to 5 show jI! 1 is a characteristic diagram for explaining the
semiconductor pressure sensitive device according to the present invention shown in FIG. 1 in
comparison with the conventional example, and FIG. 6 is a longitudinal sectional view showing an
example of the semiconductor pressure sensitive device of the conventional example. ! FIG. 6 is a
cross-sectional view showing another example of the conventional pressure-sensitive element
manufacturing apparatus shown in FIG. 1-----1-semiconductor substrate, 2-1 1 1 1 1 5%-5-tin
oxide film, 5-1 1 pressurizer, 21----1 reaction tube, 22-- ----One heater, crane-----Oxidizing gas, 畠
'----Inert gas. * IIE, Applicant Tateishi Electric Co., Ltd. Attorney Attorney I I End Page EndPage: 6
Fig. 1 Fig. 2 Fig. 3 Fig. 4 reverse fr! No skin, Shi-o 【Don't-have b Fig. 5 (A) Claw with one hand ε
(i) 【5i02 prey Page EndPage: 77, Inventors other than the above, i! 717q 任 (same as above)
name small fY · r r procedure correction book j $ :. May, 1972 Patent Executive Secretary 1,
Patent Application Patent Application No. 47-28788 / 2, title of the invention 2, title of the
invention semiconductor pressure-sensitive element and its manufacturing method / 3, person
who makes correction Related patent applicant 4 ° post code 5505, date of correction order-?
・ Spontaneous 10-character deletion 6, target of correction 7 ° EndPage: 8 page 20 line 5 of
the specification; “correct 50 VJ as“ 5 ”. As there is an error in Figure 5 (C) of the drawings
attached to the 30 drawing applications, we will resubmit the same drawings. Fig. 5 (C)
[V1EndPage: 9
Без категории
Размер файла
22 Кб
Пожаловаться на содержимое документа