JPH0691582A - Multi-joint manipulator, its manufacturing method and actuator - Google Patents

Abstract

PURPOSE:To offer a multi-joint manipulator of large power generating capability and displacement quantity and capable or being miniaturized by providing an actuator control chip array and a driving body for the actuator equipped with a driving energy supplying means correspondingly to respective joints, and allowing them to have a degree of freedom for each electronic circuit chip for each actuator control. CONSTITUTION:A driving mechanism 'a' is formed by means of forming a shape memory alloy thin film pattern 35, coated with silicone film oxide made insulation film 10, 12, 34, a heating wire pattern 26 and a polyimide film 36, on a P type low concentration semiconductor substrate 1. A pair of the shape memory alloy thin film pattern 35 of the driving mechanism body 'a' is arranged correspondingly to the respective joints 37 of a multi-joint structure body 'b' composed of joints 37 connected together at a connecting portion 38 with its electronic circuit portion placed on the top of the multi-joint structure body 'b'. The shape memory alloy thin film pattern 35 is mounted on three mounting units 39 (39a, 39b, 39b) laid across two joints 37 on both sides of the structure body 'b'. Respective joint built-in sensor are driven through this control chip array.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microminiature articulated manipulator, its manufacturing method and actuator.

[0002]

2. Description of the Related Art In recent years, attention has been focused on micromachine technology, and its application to medical microrobots is expected. For this purpose, it is essential to realize a multi-joint micromanipulator for accessing the gripper etc. to an arbitrary part. In connection with this, various studies have been reported particularly on silicon micromachining to which LSI manufacturing technology is applied. Many of these are related to micromanipulators, but the actuators used to drive these using silicon as the driver are
Neither displacement was sufficient nor the amount of generated force.

On the other hand, an actuator using a shape memory alloy is excellent in displacement amount and generated force amount, and as an articulated manipulator utilizing this, for example, JP-A-63-1
The method disclosed in Japanese Patent Publication No. 36014 is known. In this, there is shown a method of independently controlling each actuator of a multi-joint manipulator and further performing feedback control.

[0004]

However, there are many problems in making the multi-joint manipulator having such a structure significantly smaller and more multifunctional. First, as the number of joints increases, many wires are required at the base of the multi-joint manipulator in order to control them independently. Further, if a sensor is incorporated in each joint to perform the feedback control in order to accurately control the displacement of each joint, the number of wires required further increases. If a semiconductor integrated circuit chip can be incorporated in each joint, this problem can be avoided, but in order to connect the integrated circuit chip to an ordinary electric wire or flexible substrate,
Even if the chip is directly connected by wire bonding technology, a considerably large pad area is required, which is an obstacle to miniaturization.

Furthermore, wiring for connecting a sensor for feedback control is required, and the space required for this is also a factor that hinders miniaturization. in addition,
The conventional technique of constructing a manipulator by assembling a huge number of individual parts is not desirable in terms of cost and miniaturization.

The present invention has been made in view of these various problems, and has a large amount of generated force and a large amount of displacement, can be miniaturized, can significantly reduce the number of assembling steps, and can be used for feedback control. An object of the present invention is to provide an articulated manipulator capable of integrally forming a sensor and incorporating the same, and a manufacturing method thereof.

[0007]

DISCLOSURE OF THE INVENTION The present invention relates to an actuator driving body for driving each joint in an articulated manipulator having actuators at each joint, and to each driving body. And an actuator control chip array in which a plurality of drive control electronic circuit chips integrated with each other are connected to each other by flexible wiring, and a means for supplying drive energy to the selected driving body via each electronic circuit. And has at least one degree of freedom for each of the actuator control electronic circuit chips. It is an articulated manipulator in which an energy supply means to the driving body and the actuator driving body are integrally formed. Further, the driving body is a shape memory alloy, and the energy supply means is an articulated manipulator which is a heater for heating the shape memory alloy. The actuator control chip array is a multi-joint manipulator having a function of driving and reading a sensor incorporated in each joint. Further, in a multi-joint manipulator having an actuator control electronic circuit in each joint, one of the electronic circuits corresponds to a specified shape given from the outside, and the actuator of each joint is operated by a signal of a sensor incorporated in each joint. It has a function of feedback control. Further, according to the present invention, electronic circuits are formed in a plurality of regions on a semiconductor substrate, these are connected to each other by a flexible wiring region, and then the semiconductor substrate in a region other than the region where the electronic circuit is formed is removed. , A method for manufacturing an articulated manipulator forming an actuator control chip array. Further, in this method of manufacturing an articulated manipulator, a step of forming a metal thin film on the substrate through the insulating film in the flexible wiring region, a step of etching the metal thin film using a predetermined mask pattern, and Forming an insulating film, forming a reversal pattern of the mask on the insulating film, etching the insulating film on the metal thin film, and selectively laminating metal on the metal thin film by selective electroless plating. And a method for manufacturing an articulated manipulator having steps. Further, the present invention, in an actuator in which a shape memory alloy thin film processed into a predetermined shape via an insulating film is arranged above a resistor thermoelectric element, the temperature dependency of the resistance value of the resistor thermoelectric element is utilized. It controls the phase transition of the shape memory alloy thin film. In the actuator, the resistor thermoelectric element is a shape memory alloy thin film having a transformation point equal to or higher than that of the shape memory alloy thin film. According to the present invention, a semiconductor integrated circuit chip array, which is connected by flexible wiring and has a reduced thickness, is formed, and a driver and a sensor are integrally formed with this to form an extremely minute driving mechanism. Wiring formation and sensor or driver assembly
Being made by semiconductor lithography technology, no assembly is required and a highly integrated drive mechanism is obtained.

[0008]

EXAMPLE A first example of the present invention will be described with reference to FIGS. This multi-joint manipulator is constructed by incorporating a drive mechanism a and a multi-joint structure b into which an electronic circuit, a shape memory alloy and the like are integrated. First, the drive mechanism will be described according to its manufacturing procedure.

First, as shown in FIG. 1, the plane orientation is (10
0) N-type low-concentration regions 2 and 3 having a junction depth of 10 μm are formed in a line at equal intervals at a plurality of places on the P-type low-concentration semiconductor substrate 1 by using phosphorus ion implantation and thermal diffusion steps. To do. Next, as shown in FIG. 2, in each N-type low concentration region 3, an N well 4 is formed in a region where a Pch-MOSFET is formed, and a P well 5 is formed in a region where an Nch-MOSFET is formed.

Thereafter, as shown in FIG. 3, the first interlayer insulating film 1 made of a field oxide film 6, a gate electrode 7, a P-type high-concentration diffusion layer 8, an N-type high-concentration diffusion layer 9, and a silicon oxide film.
A CMOS integrated circuit is formed in each of the N type low concentration regions 3 through the steps of forming the first metal wiring layer 11 and the second interlayer insulating film 12 made of polyimide.

The CMOS integrated circuit thus formed in the N type low concentration region 3 has a circuit configuration as shown in FIG. That is, the D-type flip-flop (DFF) 13
And two switching transistors 14 each, and a terminal region 15 of the input power supply line and a terminal region 1 of the input GND line.
6, input synchronization signal line terminal area 17, input control line terminal area 18, first drive line terminal area 19, second drive line terminal area 20, output power supply line terminal area 21, output GN
A terminal area 22 for the D line, a terminal area 23 for the output synchronization signal line,
And an output control line terminal region 24. Also, N
The CMOS integrated circuit formed in the low-concentration type region 2 is shown in FIG.
In addition to the circuit configuration shown in, a signal processing circuit described later,
And an input protection circuit. The switching transistor is an enhancement type Nch-MOS.
It is a FET.

Next, as shown in FIG. 5, T is set at a predetermined position.
An i-thin film heating wire pattern 26 is formed by a Ti sputtering and lithography process. Then, as shown in FIG. 6, contact holes 27 are formed in the respective terminal regions 16 to 24 by ordinary photolithography.

Next, as shown in FIG. 7, an Al film having a thickness of 1.5 μm to be the second metal wiring layer is sputtered, and then Al is patterned by ordinary photolithography to form an N type low concentration region. The power supply wiring 2 formed by the second metal wiring layer is formed by connecting the power supply line, the GND line, the synchronization signal line, and the contact hole 27 of the control line of each adjacent electronic circuit formed.
8, GND wiring 29, synchronization signal wiring 30, control wiring 31
And a first drive wire 32 connecting one of the two heating wire patterns provided beside the first drive line and the electronic circuit, and two heating wires provided beside the second drive line and the electronic circuit Second drive wirings 33 that connect the other side of the pattern are formed. At the time of etching the second metal wiring layer, T
By using an etchant having a faster Al etching rate than that of i, Al can be etched with almost no etching of Ti.

Next, as shown in FIGS. 8 and 9, a polyimide film having a thickness of 2 μm to be the third interlayer insulating film 34 is applied and formed thereon, and a shape memory having a thickness of 50 μm is further formed thereon. An alloy thin film is formed by sputtering, and a polyimide film is applied thereon, and this is etched by a lithographic process to form a shape memory alloy thin film pattern 35 to be a driver and a polyimide film 36 thereabove.

Next, after etching and removing the third interlayer insulating film 34 and the second interlayer insulating film 12 in the region other than the regions where the electronic circuit, the wiring, and the shape memory alloy thin film pattern 35 described above are formed, The main surface of the substrate on which the shape memory alloy thin film is formed is protected by a protective film, and then a voltage of 1 V is applied to the N-type low concentration regions 2 and 3 in a 10 w% ammonia solution at 80 ° C. By ECE (electrochemical controlled etching) processing, the semiconductor substrate in the region other than the N-type low concentration region is removed by etching. In a general CMOS circuit, the power supply line is connected to the N well, so that the power supply line 28 is biased so that the N-type low concentration region 2,
Can be biased to 3.

Thereafter, the exposed region of the silicon oxide film other than the N-type low concentration region of the first interlayer insulating film 10 is removed by etching with a hydrofluoric acid solution or the like, and then the surface protective film is removed.

In this way, the wiring and heating wire pattern 26 covered with the flexible polyimide, the semiconductor region partially constituting the electronic circuit which remains below the shape memory alloy and the shape memory alloy (driving) As a result, an integrated drive mechanism body a shown in FIG. 9 is obtained.

After that, the region of the shape memory alloy portion where the heating wire heater is present is held in a bent state, heat treated at 400 ° C. for 1 hour, and then rapidly cooled to perform the shape memory treatment. At this time, all shape memory alloys in the drive mechanism store the same shape.

Next, an articulated structure b as shown in FIGS. 10 and 11 is prepared. This is MIM (metal inject
formed by an ion mold, the individual joints 37 are connected to each other via a connecting portion 38 so as to be rotatable in one direction on one plane. Further, each node 37 has three mounting portions 39 on both sides.

Then, as shown in FIG. 12, the drive mechanism a in which the electronic circuit, the shape memory alloy and the like are integrated is attached to the multi-joint structure b. As can be seen from FIG. 12, one electronic circuit portion of the drive mechanism a and a pair of shape memory alloy thin film patterns 35 provided on both sides thereof correspond to one node 37 of the multi-joint structure b. The electronic circuit portion is fixed to the upper surface of the articulated structure b.

Also, a pair of shape memory alloy thin film patterns 3
5 is attached to the three attachment portions 39 (39a, 39b, 39b) extending over the two joints 37 on both side surfaces of the multi-joint structure b by bending the drive wiring portion. That is, the shape memory alloy thin film pattern 35 is fixed at the mounting portion 39a at the left end in the figure among the three mounting portions 39a, 39b, 39b, and freely moves in the lateral direction at the other two mounting portions 39b. It is attached so that you can. Here, the portion having the heating wire heater 26 for the shape memory alloy thin film pattern is the articulated structure b.
Is arranged so as to correspond to the connection portion 38 of the. In addition, the four wirings that connect the electronic circuit parts together are
Sufficient slack is provided so that strong stress is not applied when the is bent.

In this way, the drive mechanism a and the multi-joint structure b
According to the multi-joint manipulator configured as described above, the shape memory alloy thin film patterns 35 arranged on both sides of the joint 37 are not connected to the joint 37 when heated to a temperature equal to or higher than the transformation point.
A force is applied to bend the connecting portions 38 in the opposite directions. Therefore, by heating one of the pair of shape memory alloy thin film patterns 35, the corresponding connection portion 38 is formed.
Can be bent in either direction.

Next, a case will be described in which the articulated manipulator thus constructed is controlled by the signals shown in FIG. If the number of nodes 37 is n,
The electronic circuit arranged in each node 37 of this manipulator constitutes a 2n-bit shift register. First, in the first time region, 2n pulses are input to the synchronization signal line and pulses are also input to the control signal line.

Here, paying attention to the k-th node 37 counted from the input side at the time T1 at the end of the first time domain when the input of 2n pulses is completed, the electronic circuit of this node 37 has 2 ( Since the (n−k) + 1st and 2 (n−k) + 2nd DFFs 13 are included and the control signal line when the 2 (n−k) + 1th synchronizing signal rises is in the Lo state, the kth The DFF 13 in the latter stage of the node 37 of FIG. 3 is in the Lo state, and the control signal line when the 2 (n−k) + 2nd synchronization signal rises is in the Hi state, so the DFF 13 in the preceding stage of the kth joint is in the Hi state. Becomes Therefore, the first drive line in FIG. 4 is energized, while the second drive line is not energized.

Therefore, in the second time region in which the synchronizing signal is not input, only the one of the pair of shape memory alloys arranged in the kth node 37 which is connected to the first drive line is heated and the transformation temperature is changed. The node 37 is bent in a predetermined direction over the point. While the control signal is transferred in the shift register in the first time domain, the 2 (n−k) + 1th bit is H level.
There is a moment when the i state is reached, but the length of the first time region is the second
If it is sufficiently shorter than the time region or the time required to raise the temperature of the shape memory alloy thin film pattern 35, there is no problem in practical use. If this condition is not satisfied, it can be avoided by providing a latch circuit between the DFF switching transistors. As described above, the first time region and the second time region are repeated as one unit time, and the control signal pulse in the first time region is changed, so that an arbitrary node 37 is obtained.
Can be bent in either direction.

According to this structure, the control circuit, the heating wire heater, and the drive circuit are integrally formed, and it is possible to obtain a multi-joint drive mechanism that produces a large amount of generated force and a large amount of displacement without an assembly process. Further, since the wiring of each part is also formed by the lithography technique, the size can be greatly reduced as compared with a method such as wire bonding.

In the method shown in FIG. 13, the joints 37 of the articulated manipulator can be bent in either direction according to the stored shape of the shape memory alloy. A method of controlling each node 37 in a state where it is bent at an arbitrary angle by the feedback control of 1 will be described below.

There are several possible methods for this,
First, a method of controlling the temperature of the electric heater will be described. In the example of the configuration described above, the Ti thin film was used as the heating element of the electric heater,
This is replaced with a material whose resistance value has a large temperature dependence.
Examples include conductive organic thin films and Ti with a very low transformation temperature.
-Ni alloy is mentioned. The latter becomes an austenite phase in the practical temperature range and can be used in this region because the temperature dependence of the resistance value is relatively large. Since it exhibits superelasticity, it is particularly desirable in that there is no problem of reliability of the electrothermal heater portion due to plastic deformation even if the strain of the shape memory alloy of the driving body during transformation is large.

A method of performing feedback control by temperature using the temperature dependency of the displacement amount of the shape memory alloy portion with the above structure will be described with reference to FIG. Here, as in the case of the description of FIG. 13, the multi-joint manipulator has n nodes, and the electronic circuit as a whole constitutes a 2n-bit shift register.

As can be seen from this time chart, the unit time in the control is divided into the three time regions of the first, second and third. In the first time region, 2n sync signal pulses are output, and the state of the bit at the previous stage is transferred at the first rising edge thereof. Therefore, when only one pulse is first applied to the control signal line as shown in FIG. 14 through the first time region, only one bit of each bit sequentially becomes the Hi state, and the electric heater corresponding to the bit is energized.
By monitoring the current amount at this time, the temperature can be detected from the resistance value of each electric heater. Based on the detected temperature, the electric heater to be energized is determined, and the necessary pulse is input in the second time region in the same manner as described in FIG. 13, and this state is changed to the third time region. Hold in.

Thereafter, although not shown in this time chart, 2n pulses are output to the synchronizing signal line while the control signal line is in the Lo state, and each DFF is in the Lo state for the first time region. Return to processing. If such a treatment is performed in a sufficiently short cycle, the shape memory alloy of each driving body can be maintained at a predetermined temperature by fine feedback.

Next, a modified example of the method of feedback control using a piezo-type strain sensor will be described with reference to FIG. 1 in that it is different from the embodiment described with reference to FIGS.
This will be described with reference to FIGS. First, as shown in FIG. 15, the N well 4 formed in the N type low concentration region 3 is
An electric circuit to be formed in a U-shape also in a region where a heating wire heater pattern will be formed later, and the electronic circuit formed in the N-type low-concentration diffusion layer 3 is changed as shown in FIG. This is a circuit in which a 2-bit DFF and a switching transistor are added to the circuit of FIG. 3 described above, and a first piezoresistive detection line terminal region 101 and a second piezoresistive detection line terminal region 102 are added to the added portion. Included (see FIG. 16).

Further, as shown in FIG. 17, the contact hole 27 shown in FIG. 7 is formed in the first piezoresistive detection line terminal region 1.
01 and the second piezoresistive detection line terminal region 102 and the both ends of the N well 4 formed in a U shape in the region where the heating wire heater pattern is formed later. Here, since the contact hole portions at both ends of the U-shaped N well 4 have ohmic contact with the second metal wiring layer to be formed later, the N-type high-concentration diffusion layer 9 is formed. .

Next, as shown in FIG. 18, in addition to the wiring described in FIG. 7, one of the N wells serving as two piezoresistive elements provided under the heating wire pattern is connected to the first piezoresistive detection line. The first piezoresistive detection wiring 103 connected to the contact hole 27 of the terminal region 101 and the other of N wells which are two piezoresistive elements provided under the heating wire pattern are connected to the second piezoresistive detection line terminal region 102. The second piezoresistive detection wiring 104 connected to the hole 27 is formed.

After that, the multi-joint manipulator is completed by the same procedure as shown in FIGS. ECE (el
In ectrochemical controlled etching) processing,
In this circuit configuration shown in FIG. 16, since the n-well region under the heating wire heater portion is also connected to the power supply line,
This region can be left in the same manner as the N-type low concentration region where the electronic circuit is formed.

The control method is basically the same as that shown in FIG. 14, but since the number of DFFs in the node is doubled, the number of DFFs in the first and second time regions is doubled. A sync signal pulse is required. By sequentially transferring one pulse in the first time region and monitoring the current value when the first and second piezoresistance detection wirings are in the energized state,
The amount of displacement of each shape memory alloy portion can be known from the piezoresistive effect of the N well region below the shape memory alloy portion. The electrothermal heater to be energized is determined based on the displacement of the shape memory alloy portion detected in this way, and a required pulse is input in the second time region to turn on a predetermined electrothermal heater wiring to make it electrically conductive. The state is held in the third time region.
After that, 4n pulses are output to the synchronizing signal line while the control signal line is in the Lo state, each DFF is brought into the Lo state, and then the process returns to the first time region. If such a process is performed in a sufficiently short cycle, the shape memory alloy of each driving body can be maintained at a predetermined displacement by fine feedback.

Next, regarding the method of controlling the articulated manipulator by utilizing the change in the resistance value of the shape memory alloy itself of the driving body, the difference from the embodiment described with reference to FIG. 1 to FIG. This will be described with reference to FIGS.

First, the electronic circuit included in the N-type low concentration region 3 is changed as shown in FIG. This is a circuit in which a 2-bit DFF 13 and a switching transistor 14 are further added to the circuit of FIG. 3, and the first driver resistance detection line terminal area 201 and the second driver resistance detection line terminal area 202 are added in the added parts. Is included. Here, one of the first and second driver body resistance detection line terminal regions 201 and 202 is not the input power supply line terminal region 15 and the output power supply line terminal region 21, but the separately prepared input resistance detection power supply line terminal region 203.
And the output resistance detection power supply line terminal area 204. However, although not shown, four DFFs in the circuit
The power of 13 is supplied from the input power line terminal area 15 as in the case of FIGS. 3 and 16.

Next, as shown in FIG. 20, in addition to the wiring described with reference to FIG. 7, first and second wirings of one heating wire pattern are connected to the contact holes 27 of the first driver body resistance detection line terminal area 201. The driving body resistance detection wiring 205 and the second driving body resistance detection wiring 206 connected to both sides of the other heating wire pattern and the contact holes of the second driving body resistance detection line terminal area 202.
A resistance detection wiring 207 for connecting the input resistance power supply line and the output input resistance power supply line is formed.

Next, as shown in FIGS. 21 and 22, a third interlayer insulating film 208 made of polyimide is formed, and the tips of the first and second driver body resistance detection wirings are contacted by a lithography process. A hole 209 is formed, and as in the case of FIG. 8, a shape memory alloy thin film having a thickness of 50 μm is formed thereon by sputtering, and a polyimide film is applied thereon, and this is etched by a lithography process. Then, the shape memory alloy thin film pattern 35 to be the driver and the polyimide film 36 on the pattern 35 are formed.

Thereafter, the multi-joint manipulator is completed by the same procedure as shown in FIGS. Also,
The control method is basically the same as that using the piezoresistive element described above. Here, in order to detect the resistance value of the shape memory alloy portion, a power source different from the electronic circuit and the electric heater is used because the resistance value of the shape memory alloy portion used as a driver is much higher than that of the electric heater. This is because it is so small that it may be heated when the resistance value of the shape memory alloy portion is detected, so that this is prevented.

The control method based on the temperature of the electric heater, the amount of displacement of the piezo element integrated with the driving body, and the resistance value of the shape memory alloy of the driving body has been described so far. Feedback control can also be performed.

In actuality, in order to perform such control, the temperature of the electric heater, the displacement amount of the piezo element, or the resistance of the shape memory alloy portion is obtained from the monitored current value, and further it is driven. It is necessary to convert the displacement amount of the shape memory alloy portion as the body to generate the control signal pulse. It is particularly desirable to incorporate an electronic circuit for realizing these in the electronic circuit of the first joint of the articulated manipulator (the portion of the low concentration N type region 2 in FIG. 1).
The articulated manipulator in the micro system targeted by the present invention is used as one functional unit in the whole system, but if such a high degree of signal control is possible inside the functional unit, As it is very advantageous in constructing a large-scale system. Further, by writing the information about the characteristic value peculiar to the driving body or the sensor in the ROM formed in the electronic circuit of the first joint, the versatility of the multi-joint manipulator as a functional element can be enhanced.

Up to this point, the drive mechanism using a pair of shape memory alloys that act to bend the joints in different directions has been described, but the shape memory alloys are capable of omnidirectional shape memory by special heat treatment. If this is utilized, the drive mechanism (means) can be configured by one drive body per one joint. Such an embodiment will be described with reference to FIGS. 23 to 27.

First, the electronic circuit region is formed on the semiconductor substrate 1 by the same procedure as shown in FIGS. 1 and 2, but the circuit formed in the N-type low concentration region 3 is as shown in FIG. . As is known from FIG. 23, this is a half of the circuit of FIG. 3 described above, and thus has a set of drive line terminal areas 301.

Next, as shown in FIG. 24, after forming the second interlayer insulating film 12, contact holes 302 are formed in the regions 15 to 18, 21 to 24, and 301 in FIG.

Next, as shown in FIG. 25, a power supply line for each adjacent electronic circuit and GN formed in the N type low concentration region by the lithography process of Al to be the second metal wiring layer.
Connect the contact holes of D line, sync signal line and control line,
Power supply wiring 28 and GND wiring 2 by the second metal wiring layer
9, the synchronizing signal wiring 30, the control wiring 31, and the driving wiring 303 from the terminal area 301 of the driving line are formed.

Next, as shown in FIGS. 26 and 27, after forming a third interlayer insulating film 304 made of polyimide,
Form a contact hole 305 at the tip of the drive wiring 303,
Further, an electrothermal heater pattern 30 serving as a means for supplying energy to a driver by a Ti thin film lithography process.
6 is formed, and as shown in FIG. 27, a fourth interlayer insulating film 307 made of polyimide is formed thereon.

Next, as shown in FIG. 28, after a shape memory alloy thin film is sputtered, a shape memory alloy 308 to be a driver is formed by a lithography process. After that, as described above, the main surface of the substrate on which the shape memory alloy thin film and the like are formed is protected by a protective film, and then a voltage of 1 V is applied to the N-type low concentration regions 2 and 3. While ECE
The semiconductor substrate 1 in the region other than the N-type low concentration region by the treatment
Are removed by etching. After that, the exposed region other than the N-type low concentration region of the first interlayer insulating film 10 of the silicon oxide film is removed by etching with a hydrofluoric acid solution or the like, and then the surface protective film is removed and covered with a flexible polyimide film. There is obtained a drive unit in which the wiring and the heating wire pattern, the semiconductor region which partially remains in the lower portion of the semiconductor circuit and which constitutes the electronic circuit, and the shape memory alloy formed in the upper portion are integrated. After this, the omnidirectional shape memory treatment is performed by performing heat treatment while applying appropriate deformation to the shape memory alloy. By incorporating this into an articulated structure, it can function as an articulated manipulator. About control method 1
Basically, only one joint drive unit
It is the same as explained in the figure. It goes without saying that feedback control can be performed at an arbitrary bending angle by incorporating a sensor in the manner described above.

Up to this point, the articulated manipulator that is driven by causing the shape memory alloy to store the bending displacement in the shape has been described. However, in the shape memory alloy, it is generally possible to obtain a larger force by expanding and contracting the shape memory. FIG. 29
The embodiment will be described with reference to FIGS.

First, in the same procedure as in FIGS. 1 to 7,
After forming the electronic circuit, the wiring and the electric heater, a polyimide film to be the third interlayer insulating film and a positive resist film are formed, and the resist film is exposed and developed by a photo process,
A resist pattern 402 is formed.

Thereafter, as shown in FIGS. 30 and 31,
A shape memory alloy thin film and a polyimide film are sequentially formed by sputtering, and this is etched by a lithography process to form a shape memory alloy thin film pattern 403 to be a driver and a polyimide film 404 above it.

After that, a resist pattern 4 is formed with an organic solvent or the like.
When 02 is selectively removed, the shape memory alloy thin film pattern 4 is formed as shown in FIG. 31 showing a cross section taken along line EE in FIG.
The area 03 is fixed to the electrothermal heater pattern 26 and the polyimide film 404 only at one end.

Then, an EC similar to that described above is used.
The E process and the removal of the first interlayer insulating film 10 are performed. After that, the shape memory alloy is subjected to shape memory treatment in the expansion / contraction direction, and the drive mechanism
To complete. Next, an articulated structure b as shown in FIG. 32 is prepared. This is almost the same as that shown in FIG. 10 described above, but there are four mounting portions 39 at each node 37.

Next, the drive mechanism a is attached to the multi-joint structure b as shown in FIG. This is also similar to the method shown in FIG. 12, but the pair of shape memory alloy thin film pattern portions 35 has two nodes 37 on both sides of the multi-joint structure b.
The shape memory alloy is fixed to the mounting portions 39a at both ends of the four, and the other two intermediate mounting portions 39b can freely move in the lateral direction. Here, as can be seen from FIG. 34, which is a cross-sectional view taken along line FF in FIG. 33, the portions of the electric heater and the second and third insulating layers are the shape memory alloy of the mounting portions 39a fixed at both ends. Thin film pattern portion 35
It is fixed only at one end which is fixed with respect to.

According to this structure, when one of the electric heaters is heated, the shape memory alloy in that portion is contracted, and the joint portion of the multi-joint structure b is bent. Further, since the shape memory alloy portion and the electrothermal heater portion of the driving body b are fixed at only one end, the electrothermal heater is not greatly distorted by a large displacement of the shape memory alloy.
Generally, when trying to obtain the same bending angle at the joints of the structure, contraction requires a larger strain than bending, so it is desirable to take such a measure.

Up to now, a method of forming the shape memory alloy thin film pattern 35 on the insulated electric heater portion by the sputtering and the lithographic process in order to integrally form the shape memory alloy as the driving body on the driving mechanism body has been described. However, a shape memory alloy member that has undergone shape memory treatment in advance may be attached to the insulated electric heater portion. Further, the driving body b is not limited to the shape memory alloy,
If a material that is displaced by voltage or heat generated thereby is used, electronic circuit groups connected to each other by flexible wiring, electrodes integrally formed with the electronic circuit group, or an electric heater disclosed in these examples are used. The driving energy supply means can be configured by the above.

By the way, in the above embodiments,
We have used sputtered Al thin film as the wiring, but if the number of joints is large and the total length of the multi-joint manipulator becomes long, the wiring resistance will hinder normal operation, so it is necessary to increase the wiring width, which hinders miniaturization. Will be a factor. A method for avoiding this problem will be described with reference to FIGS.
8 will be described below.

First, as shown in FIG. 34, a wiring pattern similar to that shown in FIG. 7 is formed of a Pt thin film 501 by sputtering with a thickness of about 200 nm. Next, as shown in FIG. 36 showing a cross section taken along the line GG of FIG.
02 and 1 μm of Al are formed, and Al is etched by a reverse pattern of the Pt wiring pattern to form an Al pattern 503.
To form. Next, as shown in FIG. 37, polyimide 502 is anisotropically etched by RIE using Al as a mask to form an opening 504.

After that, as shown in FIG. 38, the Al pattern 503 is selectively removed, and then Pt is removed by a mixed solution of tetramethylammonium hydroxide and copper sulfate.
Copper 505 is selectively electroless plated with a thickness of 10 μm on the exposed portion. After that, the multi-joint manipulator is completed by the same procedure as that shown in FIG. In this method, since copper, which is relatively thick and has a low resistivity, can be used as the wiring, the wiring resistance can be significantly reduced.

As described above, when the wiring resistance is significantly reduced and a bipolar transistor having a large driving capability is used for the switching Tr of the control circuit, by using an extremely fine shape memory alloy wire for the driving body, Instead of using the heater, it is possible to directly heat the shape memory alloy wire by heating. 39 and 40 show examples of conceptual configurations of the multi-joint manipulator configured by such a method, respectively. Here, the actuator control chip 6 connected to each other by the wiring 602 is connected to the articulated structure 601.
The actuator control chip array according to No. 03 is attached, and the first and second drive line terminal regions in the circuit having the same configuration as shown in FIG. 4 are directly connected to both ends of the pair of ultrafine shape memory alloy wires 604. . In FIG. 39, the multi-joint manipulator is provided on the outer periphery of the pipe-shaped rigid portion 606, and in FIG. It is housed in a pipe consisting of.

FIG. 41 shows a control circuit of the multi-joint manipulator in the case where the control of each joint of the multi-joint manipulator is not arbitrary but is sequentially performed. In FIG. 41, 60 is a resistor, (61-1) to (61-n) are depletion type MOS-FETs, and (62-1) to (62-n) are shape memory alloys (SMA). . Reference numeral 60 is a resistor that divides the input voltage by resistance and applies a voltage corresponding to the resistance division to the drains of the FETs (61-1) to (61-n).
~ (61-n) FET is a shape memory alloy (62-1).
~ (62-n) is a switching element for energizing.

In the structure shown in FIG. 41, the input voltage V is increased and V ₁ is the gate-source cutoff voltage V.
When it becomes larger than _GS, the FET of (61-1) becomes O
N, and a constant current flows through the shape memory alloy of (62-1).
In the other FETs (61-2) to (61-n), the input voltage V is divided by the resistor 60 placed in the middle, and V _{GS (OFF)} > V ₂ > V ₃ > V ₄ ...> V _n and F
ETs (61-2) to (61-n) are OFF.

When the input voltage V is further increased,
V ₂ > V _{GS (OFF) and} FET (61-2) is _turned on,
A constant current also flows through the SMA (62-2). By repeating the above, finally V ₁ > V ₂ > V ₃ >...>
V _n > V _{GS (OFF)} and SMA (62-1) to (62
-N) can be sequentially energized by the input voltage.

In this example, the shape memory alloy (SM
Although the switching operation of the FET is used to perform the energization control in A), the present invention is not limited to this, and the circuit example shown in FIG. 42 using a Zener diode as a switching element may be used.

In FIG. 42, (65-1) to (65-
n) is SMA, (63-1) to (63-n) are zener diodes, and the zener voltages of (63-1) to (63-n) are V _ZD1 , V _ZD2 , V _ZD3 , ..., V _ZDn, and V _ZD1 <V _ZD2 <V _ZD3 <... <V _ZDn . 64
Is a switching diode, and (65-1) to (65-
A constant voltage is applied to the SMA of n).

Therefore, in FIG. 42, the input voltage V
, And when V> V _ZD1 , (63-1)
Zener current flows from the Zener diode of
Energize (65-1). Further, when the input voltage V is increased and V> V _ZD2 , the Zener current flows from the Zener diode of (63-2), and the SMA (65-
Energize 2).

When this process is repeated, finally, V
> V _ZDn , and (65-1) to (65-n) SMA
Energize all. Even if the Zener current flowing from the Zener diode having a low Zener voltage increases as the input voltage V is increased, the voltage is constant due to the 64 switching diodes, so that (65-1) to (6)
All SMAs of 5-n) perform uniform expansion and contraction. From the above, SMA (65-1) to (65-
n) can be sequentially energized.

In the above, the Zener diode (63
-1) to (63-n) Zener voltage is V _ZD1 <V _ZD2
<... <V _ZDn are arranged in sequence, but by changing this order, a predetermined bending operation can be performed. From the above, when operating the articulated manipulator sequentially, it is possible to configure the SMA energization control line with only two.

[0070]

As described above, according to the present invention, a very fine articulated manipulator can be obtained, and it can be easily manufactured without performing a complicated assembly process.

[Brief description of drawings]

FIG. 1 is an explanatory diagram in which an N type low concentration region is formed on a P type low concentration semiconductor substrate.

FIG. 2 is an explanatory diagram in which a well is formed in the N-type low concentration region.

FIG. 3 is a layout explanatory view in which a CMOS integrated circuit and an interlayer insulating film are formed in the N type low concentration diffusion region.

FIG. 4 is an explanatory diagram of a configuration of a CMOS integrated circuit.

FIG. 5 is a layout diagram of a heating wire pattern.

FIG. 6 is a layout view of contact holes.

FIG. 7 is an explanatory diagram of an arrangement configuration of a second metal wiring layer.

FIG. 8 is a layout explanatory view in which a shape memory alloy thin film pattern and a polyimide film are formed.

9 is a sectional view of a laminated structure in which a shape memory alloy thin film pattern and a polyimide film are formed along line AA of FIG.

10A is a side view of the multi-joint structure, and FIG. 10B is a plan view thereof.

11 is a cross-sectional view taken along the line BB in FIG.

12A is a side view of an articulated manipulator in which a drive mechanism is attached to an articulated structure, and FIG. 12B is a plan view thereof.

FIG. 13 is a waveform diagram of a control signal of the articulated manipulator.

FIG. 14 is a waveform diagram of a signal for performing feedback control on the articulated manipulator.

FIG. 15 is a pattern explanatory diagram of a modified example.

FIG. 16 is an explanatory diagram of a configuration of an integrated circuit.

FIG. 17 is a layout view of contact holes.

FIG. 18 is a layout explanatory view in which a shape memory alloy thin film pattern and a polyimide film are formed.

FIG. 19 is an explanatory diagram of a configuration of an integrated electronic circuit.

FIG. 20 is an explanatory diagram of a wiring pattern.

FIG. 21 is an explanatory diagram of a wiring pattern.

22 is a sectional view of the laminated structure taken along the line CC in FIG.

FIG. 23 is an explanatory diagram of a configuration of an integrated electronic circuit.

FIG. 24 is an explanatory diagram of the arrangement structure of contact holes.

FIG. 25 is an explanatory diagram of a wiring structure.

FIG. 26 is an explanatory diagram of an electric heater pattern.

FIG. 27 is an explanatory view of the laminated structure taken along the line D-D in FIG. 26.

FIG. 28 is an explanatory diagram of an arrangement pattern of shape memory alloy.

FIG. 29 is an explanatory view of the arrangement of resist patterns.

FIG. 30 is an explanatory view of the layout of the shape memory alloy thin film pattern.

31 is a sectional view of the laminated structure taken along line EE in FIG. 30. FIG.

32A is a side view of the multi-joint structure, and FIG. 32B is a plan view thereof.

FIG. 33 (a) is a side view showing a drive mechanism assembled to the multi-joint structure, and FIG. 33 (b) is a plan view thereof.

34 is a sectional view taken along the line FF in FIG.

FIG. 35 is an explanatory diagram of the layout of wiring patterns.

36 is a cross-sectional view taken along the line GG in FIG.

FIG. 37 is a cross-sectional view of a laminated structure in which an opening is formed.

FIG. 38 is a sectional view of a laminated structure in which electroless plating is applied to the opening.

FIG. 39A is a perspective view of another multi-joint manipulator, and FIG. 39B is a sectional view taken along line HH in FIG.

FIG. 40 (a) is a perspective view of still another multi-joint manipulator, and FIG. 40 (b) is a sectional view taken along line I-I in FIG. 40 (a).

FIG. 41 is an explanatory diagram of a configuration of a control circuit.

FIG. 42 is a configuration explanatory view of another control circuit.

[Explanation of symbols]

1 ... Semiconductor substrate, 13 ... D flip-flop, 14 ...
Switching transistor, 26 ... Heating wire pattern,
28 ... Power wiring, 35 ... Shape memory alloy thin film pattern, 3
7 ... Section, 38 ... Connection part, a ... Drive mechanism, b ... Articulated structure.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshimasa Kawai 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd.

Claims (9)

[Claims] 1. In a multi-joint manipulator having an actuator at each joint, an actuator driver for driving each joint and a plurality of drive controllers corresponding to each driver and integrated with it. An actuator control chip array in which electronic circuit chips are connected to each other by flexible wiring, and means for supplying drive energy to the selected driving body via each of the electronic circuits are provided. An articulated manipulator having at least one degree of freedom for each. 2. The multi-joint manipulator according to claim 1, wherein the means for supplying energy to the driving body and the driving body for the actuator are integrally formed. 3. The articulated manipulator according to claim 1, wherein the driving body is a shape memory alloy, and the energy supply means is a heater for heating the shape memory alloy. 4. The multi-joint manipulator according to claim 1, wherein the actuator control chip array has a function of driving and reading a sensor incorporated in each joint. 5. A multi-joint manipulator having an actuator controlling electronic circuit in each joint, wherein one of the electronic circuits corresponds to a specified shape given from the outside by a signal from a sensor incorporated in each joint. A multi-joint manipulator having a function of performing feedback control of a joint actuator. 6. An electronic circuit is formed in a plurality of regions on a semiconductor substrate, these are mutually connected by a flexible wiring region, and then the semiconductor substrate in a region other than the region where the electronic circuit is formed is removed. A method for manufacturing an articulated manipulator, comprising forming an actuator control chip array. 7. A step of forming a metal thin film on the substrate with the flexible wiring region via an insulating film, a step of etching the metal thin film using a predetermined mask pattern, and forming an insulating film thereon. Forming a reverse pattern of the mask thereon, etching the insulating film on the metal thin film, and selectively laminating metal on the metal thin film by selective electroless plating. The method for manufacturing an articulated manipulator according to claim 6, which is characterized in that. 8. An actuator in which a shape memory alloy thin film processed into a predetermined shape is arranged on an upper portion of a resistor thermoelectric element with an insulating film interposed therebetween, utilizing the temperature dependence of the resistance value of the resistor thermoelectric element. An actuator characterized by controlling the phase transition of the shape memory alloy thin film. 9. The actuator according to claim 8, wherein the resistor thermoelectric element is a shape memory alloy thin film having a transformation point equal to or higher than that of the shape memory alloy thin film.